2024 100404

B. Tech 4th Semester Examination, 2024

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct option/answer the following (Any seven question only):

Q1.1

The function $ f:R \rightarrow R $ defined by $ f(x)=x^3+5 $

a)

One-One but not onto

b)

Onto but not One-One

c)

Both One-One and Onto

d)

None of these

Q1.2

Consider the following relation R on a set $ A=\{1,2,3,4\} $: R = {(1,1), (1, 3), (3, 2), (2, 2), (3, 3), (3, 1), (2, 3), (1, 4), (4, 4)} Then

a)

Reflexive

b)

Symmetric

c)

Transitive

d)

Equivalence

Q1.3

Out of the following which of these integers is not prime?

a)

23

b)

59

c)

21

d)

71

Q1.4

The Greatest common divisor of 0 and 11

a)

0

b)

1

c)

11

d)

Does not exist

Q1.5

Suppose G is a group with a binary operation * defined by $ a*b=a+b+1 $, for $ a, b \in G $ then

a)

Identity element = -1

b)

Identity element = 1

c)

Identity element = -2

d)

Identity element = 2

Q1.6

The field which contains at least _____ element/elements

a)

0

b)

1

c)

2

d)

3

Q1.7

The set of integers with respect to addition is

a)

Abelian group

b)

Cyclic group

c)

Both (i) and (ii)

d)

None of these

Q1.8

The total number of edges in a complete graph of n vertices is

a)

nn

b)

n2\frac{n}{2}

c)

n21n^2-1

d)

n(n1)2\frac{n(n-1)}{2}

Q1.9

In any undirected graph, the sum of degrees of all vertices

a)

must be even

b)

is a twice the number of edges

c)

must be odd

d)

Both (i) and (ii)

Q1.10

$ (p \rightarrow q) \wedge (r \rightarrow q) $ is equivalent to

a)

(pr)q(p \vee r) \rightarrow q

b)

p(rp)p \vee (r \rightarrow p)

c)

p(rq)p \vee (r \rightarrow q)

d)

p(qr)p \rightarrow (q \rightarrow r)

Q.2 Solve both questions :

Q2.1

Given $ A=\{1,2,3\} $, $ B=\{7,8\} $ and $ R=\{(1,7), (2, 7), (1, 8), (3, 8)\} $, find $ R^{-1} $ (inverse of R) and $ R' $ complement of R.

Q2.2

Consider $ A=B=C=R $ set of real numbers and let $ f:A \rightarrow B $, $ g: B \rightarrow C $ defined by $ f(x)=x+9 $ and $ g(y)=y^2+3 $ find the following composition functions: $ (f \circ g)(a) $, $ (g \circ f)(a) $, $ (g \circ f)(x) $, $ (f \circ g)(-3) $.

Q.3 Solve both questions :

Q3.1

What is the negation of each of the following propositions? (i) Today is Tuesday (ii) A cow is an animal (iii) No one wants to buy my house

Q3.2

Determine the truth value of each of the following statements (i) $ 4+3=7 $ and $ 6+2=8 $ (ii) $ 2+3=4 $ and $ 3+1=2 $

Q.4 Solve both questions :

Q4.1

Show that the set of rational numbers Q forms an abelian group.

Q4.2

Define a ring, give an example of a commutative ring without zero divisors and a non-commutative ring with identity.

Q.5 Solve both questions :

Q5.1

Describe the Fundamental Theorem of Arithmetic. Factorize the number '324' and represent it as a product of primes.

Q5.2

Use the Euclidean algorithm to find the greatest common divisor of each pair of integers, (i) 60, 90 (ii) 414, 662

Q.6 Solve both questions :

Q6.1

Describe a graph model that can be used to represent all forms of electronic communication between two people in a single graph. What kind of graph is needed?

Q6.2

Explain the complete graph and prove that $ k_5 $ (complete graph) is a nonplanar graph.

Q.7 Solve both questions :

Q7.1

Explain the congruence relation. Let $ n $ be a positive integer then: (i) If $ a \equiv b \pmod{n} $, then $ b \equiv a \pmod{n} $ (ii) If $ a \equiv b \pmod{n} $ and $ b \equiv c \pmod{n} $, then $ a \equiv c \pmod{n} $.

Q7.2

Show that $ p \Leftrightarrow q \equiv (p \Rightarrow q) \wedge (q \Rightarrow p) $

Q.8 Solve both questions :

Q8.1

Write short notes of the following: (i) Eulerian Graph (ii) Graph Coloring

Q8.2

Write short notes of the following: (i) Chromatic number (ii) Perfect Graph

Q.9 Solve both questions :

Q9.1

What is the field? Show that $ (Q, +, \times) $ is a field.

Q9.2

If in a ring R with $ (xy)^2=x^2y^2 $ for all $ x, y \in R $, then R is commutative.


2024 V5 100404

B. Tech 4th Semester Examination, 2024

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct option/answer the following (Any seven question only):

Q1.1

The function $ f:R \rightarrow R $ defined by $ f(x)=x^3+5 $

a)

One-One but not onto

b)

Onto but not One-One

c)

Both One-One and Onto

d)

None of these

Q1.2

Consider the following relation R on a set $ A=\{1,2,3,4\} $: R = {(1,1), (1, 3), (3, 2), (2, 2), (3, 3), (3, 1), (2, 3), (1, 4), (4, 4)} Then

a)

Reflexive

b)

Symmetric

c)

Transitive

d)

Equivalence

Q1.3

Out of the following which of these integers is not prime?

a)

23

b)

59

c)

21

d)

71

Q1.4

The Greatest common divisor of 0 and 11

a)

0

b)

1

c)

11

d)

Does not exist

Q1.5

Suppose G is a group with a binary operation * defined by $ a*b=a+b+1 $, for $ a, b \in G $ then

a)

Identity element = -1

b)

Identity element = 1

c)

Identity element = -2

d)

Identity element = 2

Q1.6

The field which contains at least _____ element/elements

a)

0

b)

1

c)

2

d)

3

Q1.7

The set of integers with respect to addition is

a)

Abelian group

b)

Cyclic group

c)

Both (i) and (ii)

d)

None of these

Q1.8

The total number of edges in a complete graph of n vertices is

a)

nn

b)

n2\frac{n}{2}

c)

n21n^2-1

d)

n(n1)2\frac{n(n-1)}{2}

Q1.9

In any undirected graph, the sum of degrees of all vertices

a)

must be even

b)

is a twice the number of edges

c)

must be odd

d)

Both (i) and (ii)

Q1.10

$ (p \rightarrow q) \wedge (r \rightarrow q) $ is equivalent to

a)

(pr)q(p \vee r) \rightarrow q

b)

p(rp)p \vee (r \rightarrow p)

c)

p(rq)p \vee (r \rightarrow q)

d)

p(qr)p \rightarrow (q \rightarrow r)

Q.2 Solve both questions :

Q2.1

Given $ A=\{1,2,3\} $, $ B=\{7,8\} $ and $ R=\{(1,7), (2, 7), (1, 8), (3, 8)\} $, find $ R^{-1} $ (inverse of R) and $ R' $ complement of R.

Q2.2

Consider $ A=B=C=R $ set of real numbers and let $ f:A \rightarrow B $, $ g: B \rightarrow C $ defined by $ f(x)=x+9 $ and $ g(y)=y^2+3 $ find the following composition functions: $ (f \circ g)(a) $, $ (g \circ f)(a) $, $ (g \circ f)(x) $, $ (f \circ g)(-3) $.

Q.3 Solve both questions :

Q3.1

What is the negation of each of the following propositions? (i) Today is Tuesday (ii) A cow is an animal (iii) No one wants to buy my house

Q3.2

Determine the truth value of each of the following statements (i) $ 4+3=7 $ and $ 6+2=8 $ (ii) $ 2+3=4 $ and $ 3+1=2 $

Q.4 Solve both questions :

Q4.1

Show that the set of rational numbers Q forms an abelian group.

Q4.2

Define a ring, give an example of a commutative ring without zero divisors and a non-commutative ring with identity.

Q.5 Solve both questions :

Q5.1

Describe the Fundamental Theorem of Arithmetic. Factorize the number '324' and represent it as a product of primes.

Q5.2

Use the Euclidean algorithm to find the greatest common divisor of each pair of integers, (i) 60, 90 (ii) 414, 662

Q.6 Solve both questions :

Q6.1

Describe a graph model that can be used to represent all forms of electronic communication between two people in a single graph. What kind of graph is needed?

Q6.2

Explain the complete graph and prove that $ k_5 $ (complete graph) is a nonplanar graph.

Q.7 Solve both questions :

Q7.1

Explain the congruence relation. Let $ n $ be a positive integer then: (i) If $ a \equiv b \pmod{n} $, then $ b \equiv a \pmod{n} $ (ii) If $ a \equiv b \pmod{n} $ and $ b \equiv c \pmod{n} $, then $ a \equiv c \pmod{n} $.

Q7.2

Show that $ p \Leftrightarrow q \equiv (p \Rightarrow q) \wedge (q \Rightarrow p) $

Q.8 Solve both questions :

Q8.1

Write short notes of the following: (i) Eulerian Graph (ii) Graph Coloring

Q8.2

Write short notes of the following: (i) Chromatic number (ii) Perfect Graph

Q.9 Solve both questions :

Q9.1

What is the field? Show that $ (Q, +, \times) $ is a field.

Q9.2

If in a ring R with $ (xy)^2=x^2y^2 $ for all $ x, y \in R $, then R is commutative.


2023 100404

End Semester Examination - 2023

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Write the answer of the following (Any seven question only):

Q1.1

Let A be the set odd positive integers less than 10. Then cardinality of A, |A| is

a)

5

b)

9

c)

6

d)

4

Q1.2

If m is the number of objects (pigeons) and n is the number of boxes (pigeonholes), then the function is both one-to-one and onto if

a)

m < n

b)

m=nm = n

c)

m > n

d)

none of these

Q1.3

If $ A \times B = B \times A $, (Where A and B are general matrices) then

a)

A=ϕA = \phi

b)

A=BA = B'

c)

B=AB = A

d)

A=BA' = B

Q1.4

A partial ordered relation is transitive, reflexive and

a)

Anti symmetric

b)

bi symmetric

c)

anti reflexive

d)

asymmetric

Q1.5

If B is a Boolean Algebra, then which of the following is true

a)

B is a finite but complemented lattice

b)

B is a finite, complemented and distributive lattice

c)

B is a finite, Distributive but not complemented lattice

d)

B is not distributive lattice

Q1.6

$ P \rightarrow q $ is logically equivalent to

a)

qp-q \rightarrow p

b)

Pq-P \rightarrow q

c)

Pq-P \wedge q

d)

pq-p \vee q

Q1.7

If $ f(x) = \cos x $ and $ g(x) = x^3 $ then $ (f \circ g)(x) $ is

a)

(cosx)3(\cos x)^3

b)

cos3x\cos 3x

c)

x(cosx)3x^{(\cos x)^3}

d)

cos(x3)\cos(x^3)

Q1.8

The number of distinguishable permutations of the letters in the word BANANA are

a)

60

b)

36

c)

20

d)

10

Q1.9

Which of the following pair is not congruent modulo 7?

a)

10, 24

b)

25, 56

c)

-31, -15

d)

-64, -15

Q1.10

Let $ N=\{1,2,3,........\} $ be ordered by divisibility, which of the following subset is totally ordered

a)

(2, 6, 24)

b)

(3, 5, 15)

c)

(2, 9, 16)

d)

(4, 15, 30)

Q.2 Solve both questions :

Q2.1

Let $ A = B = \{x | -1 \le x \le 1\} $ for each of the following functions state where it is injective, surjective or bijective: i) $ g(x) = \sin \pi x $ ii) $ b(x) = \frac{2x}{3} $

Q2.2

Let $ f(x) = x+2 $, $ g(x) = x-2 $, $ h(x) = 3x $ find (i) $ f \circ g $ (ii) $ f \circ g \circ h $

Q.3 Solve both questions :

Q3.1

Find the power set of each of these sets: i) $ \{a,b\} $ ii) $ \{\phi, \{\phi\}\} $

Q3.2

Use Cantor's diagonal argument to prove that set F of all functions $ f: (0,1) \rightarrow R $ has larger Cardinality than |R|.

Q.4 Solve this question :

Q4.1

Determine if the sets are countable or uncountable: a.) the set A of all function $ g: Z_{+} \rightarrow Z_{+} $ b.) The set B of all functions $ f: Z_{+} \rightarrow \{0,1\} $

Q.5 Solve this question :

Q5.1

Prove the following by using the principle of mathematical induction for all $ n \in N $: $ 1^3 + 2^3 + 3^3 + \dots + n^3 = \left(\frac{n(n+1)}{2}\right)^2 $

Q.6 Solve this question :

Q6.1

State and prove Division algorithm theorem well-ordering principle.

Q.7 Solve both questions :

Q7.1

Check the validity of the following argument all integers are rational numbers. Some integers are powers of 5. Therefore, some rational numbers are powers of 5.

Q7.2

A grocery store employee is stocking apples. Each apple is a different color. There are 10 apples left in the box and the employee pulls out 2 of them at random. What is the probability that the employee pulls out one pink apple and yellow apple?

Q.8 Solve this question :

Q8.1

Let $ \Psi: G \rightarrow H $ be a homomorphism of groups. Show that if $ a \in G $ has order n, then $ \Psi(a) \in H $ has order dividing n.

Q.9 Solve both questions :

Q9.1

Consider the given graph. (a) Does a Hamiltonian path exist? If so describe it. If not say why not.

(b) Does an Eulerian path exist? If so describe it. If not say why not.

Question Diagram

2023 V4 100404

End Semester Examination - 2023

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Write the answer of the following (Any seven question only):

Q1.1

Let A be the set odd positive integers less than 10. Then cardinality of A, |A| is

a)

5

b)

9

c)

6

d)

4

Q1.2

If m is the number of objects (pigeons) and n is the number of boxes (pigeonholes), then the function is both one-to-one and onto if

a)

m < n

b)

m=nm = n

c)

m > n

d)

none of these

Q1.3

If $ A \times B = B \times A $, (Where A and B are general matrices) then

a)

A=ϕA = \phi

b)

A=BA = B'

c)

B=AB = A

d)

A=BA' = B

Q1.4

A partial ordered relation is transitive, reflexive and

a)

Anti symmetric

b)

bi symmetric

c)

anti reflexive

d)

asymmetric

Q1.5

If B is a Boolean Algebra, then which of the following is true

a)

B is a finite but complemented lattice

b)

B is a finite, complemented and distributive lattice

c)

B is a finite, Distributive but not complemented lattice

d)

B is not distributive lattice

Q1.6

$ P \rightarrow q $ is logically equivalent to

a)

qp-q \rightarrow p

b)

Pq-P \rightarrow q

c)

Pq-P \wedge q

d)

pq-p \vee q

Q1.7

If $ f(x) = \cos x $ and $ g(x) = x^3 $ then $ (f \circ g)(x) $ is

a)

(cosx)3(\cos x)^3

b)

cos3x\cos 3x

c)

x(cosx)3x^{(\cos x)^3}

d)

cos(x3)\cos(x^3)

Q1.8

The number of distinguishable permutations of the letters in the word BANANA are

a)

60

b)

36

c)

20

d)

10

Q1.9

Which of the following pair is not congruent modulo 7?

a)

10, 24

b)

25, 56

c)

-31, -15

d)

-64, -15

Q1.10

Let $ N=\{1,2,3,........\} $ be ordered by divisibility, which of the following subset is totally ordered

a)

(2, 6, 24)

b)

(3, 5, 15)

c)

(2, 9, 16)

d)

(4, 15, 30)

Q.2 Solve both questions :

Q2.1

Let $ A = B = \{x | -1 \le x \le 1\} $ for each of the following functions state where it is injective, surjective or bijective: i) $ g(x) = \sin \pi x $ ii) $ b(x) = \frac{2x}{3} $

Q2.2

Let $ f(x) = x+2 $, $ g(x) = x-2 $, $ h(x) = 3x $ find (i) $ f \circ g $ (ii) $ f \circ g \circ h $

Q.3 Solve both questions :

Q3.1

Find the power set of each of these sets: i) $ \{a,b\} $ ii) $ \{\phi, \{\phi\}\} $

Q3.2

Use Cantor's diagonal argument to prove that set F of all functions $ f: (0,1) \rightarrow R $ has larger Cardinality than |R|.

Q.4 Solve this question :

Q4.1

Determine if the sets are countable or uncountable: a.) the set A of all function $ g: Z_{+} \rightarrow Z_{+} $ b.) The set B of all functions $ f: Z_{+} \rightarrow \{0,1\} $

Q.5 Solve this question :

Q5.1

Prove the following by using the principle of mathematical induction for all $ n \in N $: $ 1^3 + 2^3 + 3^3 + \dots + n^3 = \left(\frac{n(n+1)}{2}\right)^2 $

Q.6 Solve this question :

Q6.1

State and prove Division algorithm theorem well-ordering principle.

Q.7 Solve both questions :

Q7.1

Check the validity of the following argument all integers are rational numbers. Some integers are powers of 5. Therefore, some rational numbers are powers of 5.

Q7.2

A grocery store employee is stocking apples. Each apple is a different color. There are 10 apples left in the box and the employee pulls out 2 of them at random. What is the probability that the employee pulls out one pink apple and yellow apple?

Q.8 Solve this question :

Q8.1

Let $ \Psi: G \rightarrow H $ be a homomorphism of groups. Show that if $ a \in G $ has order n, then $ \Psi(a) \in H $ has order dividing n.

Q.9 Solve both questions :

Q9.1

Consider the given graph. (a) Does a Hamiltonian path exist? If so describe it. If not say why not.

(b) Does an Eulerian path exist? If so describe it. If not say why not.

Question Diagram

2022 100404

B.Tech 4th Semester Exam., 2022 (New Course)

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct answer of the following (any seven):

Q1.1

The statement $ (\sim P \leftrightarrow Q) \wedge \sim Q $ is true, when

a)

P: True, Q: False

b)

P: True, Q: True

c)

P: False, Q: True

d)

P: False, Q: False

Q1.2

Which of the following statements regarding sets is false?

a)

AA=AA \cap A = A

b)

AA=AA \cup A = A

c)

A(BC)=(AB)(AC)A - (B \cap C) = (A - B) \cup (A - C)

d)

(AB)=AB(A \cup B)' = A' \cup B'

Q1.3

What is the induction hypothesis assumption for the inequality $ m! > 2^m $ where $ m \ge 4 $?

a)

For m=km = k, (k+1)! > 2^k holds

b)

For m=km = k, k! > 2^k holds

c)

For m=km = k, k! > 3^k holds

d)

For m=km = k, k! > 2^{k+1} holds

Q1.4

A simple graph can have

a)

multiple edges

b)

self-loops

c)

parallel edges

d)

no multiple edges, self-loops and parallel edges

Q1.5

An undirected graph has 8 vertices labelled 1, 2, ..., 8 and 31 edges. Vertices 1, 3, 5, 7 have degree 8 and vertices 2, 4, 6, 8 have degree 7. What is the degree of vertex 8?

a)

15

b)

8

c)

5

d)

23

Q1.6

A graph which has the same number of edges as its complement must have number of vertices congruent to ___ or ___ modulo 4 (for integral values of number of edges).

a)

6k,6k16k, 6k-1

b)

4k,4k+14k, 4k+1

c)

k,k+2k, k+2

d)

2k+1,k2k+1, k

Q1.7

A graph which consists of disjoint union of trees is called

a)

bipartite graph

b)

forest

c)

caterpillar tree

d)

labelled tree

Q1.8

Which of the following two sets are equal?

a)

A={1,2}A = \{1, 2\} and B={1}B = \{1\}

b)

A={1,2}A = \{1, 2\} and B={1,2,3}B = \{1, 2, 3\}

c)

A={1,2,3}A = \{1, 2, 3\} and B={2,1,3}B = \{2, 1, 3\}

d)

A={1,2,4}A = \{1, 2, 4\} and B={1,2,3}B = \{1, 2, 3\}

Q1.9

If $ C_n $ is the nth cyclic graph, where $ n > 3 $ and n is odd, determine the value of $ X(C_n) $

a)

32572

b)

16631

c)

3

d)

310

Q1.10

The number of edges in a regular graph of degree 46 and 8 vertices is

a)

347

b)

230

c)

184

d)

186

Q.2 Solve both questions :

Q2.1

Let $ D = \{-48, -14, -8, 0, 1, 3, 16, 23, 26, 32, 36\} $. Determine which of the following statements are true and which are false. Provide counterexamples for those statements that are false.
(i) $ \forall x \in D $, if x is odd, then $ x > 0 $
(ii) $ \forall x \in D $, if x is less than 0, then x is even
(iii) $ \forall x \in D $, if x is even, then $ x \le 0 $

Q2.2

Indicate which of the following statements are true and which are false. Justify your answers as best you can:
(i) $ \forall x \in Z^+ $, $ \exists y \in Z^+ $ such that $ x = y + 1 $
(ii) $ \forall x \in Z $, $ \exists y \in Z $ such that $ x = y + 1 $
(iii) $ \exists x \in R $ such that $ \forall y \in R $, $ x = y + 1 $
(iv) $ \forall x \in R^+ $, $ \exists y \in R^+ $ such that $ xy = 1 $
(v) $ \forall x \in R $, $ \exists y \in R $ such that $ xy = 1 $
(vi) $ \forall x \in Z^+ $ and $ \forall y \in Z^+ $ $ \exists z \in Z^+ $ such that $ z = x - y $
(vii) $ \forall x \in Z $ and $ \forall y \in Z $, $ \exists z \in Z $ such that $ z = x - y $
(viii) $ \exists u \in R^+ $ such that $ \forall v \in R^+ $, $ uv < v $

Q.3 Solve both questions :

Q3.1

Prove the following:
(i) There is a real number x such that $ x > 1 $ and $ 2^x > x^{10} $.
(ii) There is an integer n such that $ 2n^2 - 5n + 2 $ is prime.

Q3.2

Disprove that for all real numbers a and b, if $ a < b $, then $ a^2 < b^2 $.

Q.4 Solve all three questions :

Q4.1

Show that $ p \vee (q \wedge r) $ and $ (p \vee q) \wedge (p \vee r) $ are logically equivalent. This is the distributive law of disjunction over conjunction.

Q4.2

Find the greatest common divisor of 414 and 662 using the Euclidean algorithm.

Q4.3

If a and b are positive integers, then prove that there exists integers s and t such that $ gcd(a,b) = sa + tb $.

Q.5 Solve both questions :

Q5.1

Use mathematical induction to prove this formula for the sum of a finite number of terms of a geometric progression with initial term a and common ratio r:
$ \sum_{j=0}^{n} ar^j = a + ar + ar^2 + \cdots + ar^n = \frac{ar^{n+1}-a}{r-1} $ when $ r \ne 1 $, where n is a non-negative integer.

Q5.2

Write short notes on the following:
(i) Forward proof
(ii) Disjunctive and conjunctive normal form
(iii) Fundamental theorem of arithmetic

Q.6 Solve both questions :

Q6.1

An odd number of people stand in a yard at mutually distinct distances. At the same time each person throws a pie at their nearest neighbour, hitting this person. Use mathematical induction to show that there is at least one survivor, that is, at least one person who is not hit by a pie.

Q6.2

Prove Bernoulli's inequality that if $ h > -1 $, then $ 1 + nh \le (1 + h)^n $ for all non-negative integers n.

Q.7 What is pigeonhole principle? Using it, prove the following:

Q7.1

What is pigeonhole principle? Using it, prove the following:
During a month with 30 days, a baseball team plays at least one game a day, but no more than 45 games. Show that there must be a period of some number of consecutive days during which the team must play exactly 14 games.

Q7.2

What is pigeonhole principle? Using it, prove the following:
The sequence 8, 11, 9, 1, 4, 6, 12, 10, 5, 7 contains 10 terms. Note that $ 10 = 3^2 + 1 $. There are four strictly increasing subsequences of length four, namely, 1, 4, 6, 12; 1, 4, 6, 7; 1, 4, 6, 10; and 1, 4, 5, 7. There is also a strictly decreasing subsequence of length four, namely, 11, 9, 6, 5.

Q.8 Solve all questions :

Q8.1

In a Round-Robin tournament, the Tigers beat the Blue Jays, the Tigers beat the Cardinals, the Tigers beat the Orioles, the Blue Jays beat the Cardinals, the Blue Jays beat the Orioles and the Cardinals beat the Orioles. Model this outcome with a directed graph.

Q8.2

Let $ G=(V,E) $ be a simple graph. Let R be the relation on V consisting of pairs of vertices (u, v) such that there is a path from u to v or such that $ u = v $. Show that R is an equivalence relation.

Q8.3

Determine whether the following given pair of directed graphs, shown in Fig. 1 and Fig. 2, are isomorphic or not. Exhibit an isomorphism or provide a rigorous argument that none exists.

Question Diagram

Q.9 Solve all questions :

Q9.1

Use pseudocode to describe an algorithm for determining the value of a game tree when both players follow a minmax strategy.

Q9.2

Suppose that $ T_1 $ and $ T_2 $ are spanning trees of a simple graph G. Moreover, suppose that $ e_1 $ is an edge in $ T_1 $ that is not in $ T_2 $. Show that there is an edge $ e_2 $ in $ T_2 $ that is not in $ T_1 $ such that $ T_1 $ remains a spanning tree if $ e_1 $ is removed from it and $ e_2 $ is added to it, and $ T_2 $ remains a spanning tree if $ e_2 $ is removed from it and $ e_1 $ is added to it.

Q9.3

Show that a degree-constrained spanning tree of a simple graph in which each vertex has degree not exceeding 2 consists of a single Hamiltonian path in the graph.


2022 V4 100404

B.Tech 4th Semester Exam., 2022 (New Course)

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct answer of the following (any seven):

Q1.1

The statement $ (\sim P \leftrightarrow Q) \wedge \sim Q $ is true, when

a)

P: True, Q: False

b)

P: True, Q: True

c)

P: False, Q: True

d)

P: False, Q: False

Q1.2

Which of the following statements regarding sets is false?

a)

AA=AA \cap A = A

b)

AA=AA \cup A = A

c)

A(BC)=(AB)(AC)A - (B \cap C) = (A - B) \cup (A - C)

d)

(AB)=AB(A \cup B)' = A' \cup B'

Q1.3

What is the induction hypothesis assumption for the inequality $ m! > 2^m $ where $ m \ge 4 $?

a)

For m=km = k, (k+1)! &gt; 2^k holds

b)

For m=km = k, k! &gt; 2^k holds

c)

For m=km = k, k! &gt; 3^k holds

d)

For m=km = k, k! &gt; 2^{k+1} holds

Q1.4

A simple graph can have

a)

multiple edges

b)

self-loops

c)

parallel edges

d)

no multiple edges, self-loops and parallel edges

Q1.5

An undirected graph has 8 vertices labelled 1, 2, ..., 8 and 31 edges. Vertices 1, 3, 5, 7 have degree 8 and vertices 2, 4, 6, 8 have degree 7. What is the degree of vertex 8?

a)

15

b)

8

c)

5

d)

23

Q1.6

A graph which has the same number of edges as its complement must have number of vertices congruent to ___ or ___ modulo 4 (for integral values of number of edges).

a)

6k,6k16k, 6k-1

b)

4k,4k+14k, 4k+1

c)

k,k+2k, k+2

d)

2k+1,k2k+1, k

Q1.7

A graph which consists of disjoint union of trees is called

a)

bipartite graph

b)

forest

c)

caterpillar tree

d)

labelled tree

Q1.8

Which of the following two sets are equal?

a)

A={1,2}A = \{1, 2\} and B={1}B = \{1\}

b)

A={1,2}A = \{1, 2\} and B={1,2,3}B = \{1, 2, 3\}

c)

A={1,2,3}A = \{1, 2, 3\} and B={2,1,3}B = \{2, 1, 3\}

d)

A={1,2,4}A = \{1, 2, 4\} and B={1,2,3}B = \{1, 2, 3\}

Q1.9

If $ C_n $ is the nth cyclic graph, where $ n > 3 $ and n is odd, determine the value of $ X(C_n) $

a)

32572

b)

16631

c)

3

d)

310

Q1.10

The number of edges in a regular graph of degree 46 and 8 vertices is

a)

347

b)

230

c)

184

d)

186

Q.2 Solve both questions :

Q2.1

Let $ D = \{-48, -14, -8, 0, 1, 3, 16, 23, 26, 32, 36\} $. Determine which of the following statements are true and which are false. Provide counterexamples for those statements that are false.
(i) $ \forall x \in D $, if x is odd, then $ x > 0 $
(ii) $ \forall x \in D $, if x is less than 0, then x is even
(iii) $ \forall x \in D $, if x is even, then $ x \le 0 $

Q2.2

Indicate which of the following statements are true and which are false. Justify your answers as best you can:
(i) $ \forall x \in Z^+ $, $ \exists y \in Z^+ $ such that $ x = y + 1 $
(ii) $ \forall x \in Z $, $ \exists y \in Z $ such that $ x = y + 1 $
(iii) $ \exists x \in R $ such that $ \forall y \in R $, $ x = y + 1 $
(iv) $ \forall x \in R^+ $, $ \exists y \in R^+ $ such that $ xy = 1 $
(v) $ \forall x \in R $, $ \exists y \in R $ such that $ xy = 1 $
(vi) $ \forall x \in Z^+ $ and $ \forall y \in Z^+ $ $ \exists z \in Z^+ $ such that $ z = x - y $
(vii) $ \forall x \in Z $ and $ \forall y \in Z $, $ \exists z \in Z $ such that $ z = x - y $
(viii) $ \exists u \in R^+ $ such that $ \forall v \in R^+ $, $ uv < v $

Q.3 Solve both questions :

Q3.1

Prove the following:
(i) There is a real number x such that $ x > 1 $ and $ 2^x > x^{10} $.
(ii) There is an integer n such that $ 2n^2 - 5n + 2 $ is prime.

Q3.2

Disprove that for all real numbers a and b, if $ a < b $, then $ a^2 < b^2 $.

Q.4 Solve all three questions :

Q4.1

Show that $ p \vee (q \wedge r) $ and $ (p \vee q) \wedge (p \vee r) $ are logically equivalent. This is the distributive law of disjunction over conjunction.

Q4.2

Find the greatest common divisor of 414 and 662 using the Euclidean algorithm.

Q4.3

If a and b are positive integers, then prove that there exists integers s and t such that $ gcd(a,b) = sa + tb $.

Q.5 Solve both questions :

Q5.1

Use mathematical induction to prove this formula for the sum of a finite number of terms of a geometric progression with initial term a and common ratio r:
$ \sum_{j=0}^{n} ar^j = a + ar + ar^2 + \cdots + ar^n = \frac{ar^{n+1}-a}{r-1} $ when $ r \ne 1 $, where n is a non-negative integer.

Q5.2

Write short notes on the following:
(i) Forward proof
(ii) Disjunctive and conjunctive normal form
(iii) Fundamental theorem of arithmetic

Q.6 Solve both questions :

Q6.1

An odd number of people stand in a yard at mutually distinct distances. At the same time each person throws a pie at their nearest neighbour, hitting this person. Use mathematical induction to show that there is at least one survivor, that is, at least one person who is not hit by a pie.

Q6.2

Prove Bernoulli's inequality that if $ h > -1 $, then $ 1 + nh \le (1 + h)^n $ for all non-negative integers n.

Q.7 What is pigeonhole principle? Using it, prove the following:

Q7.1

What is pigeonhole principle? Using it, prove the following:
During a month with 30 days, a baseball team plays at least one game a day, but no more than 45 games. Show that there must be a period of some number of consecutive days during which the team must play exactly 14 games.

Q7.2

What is pigeonhole principle? Using it, prove the following:
The sequence 8, 11, 9, 1, 4, 6, 12, 10, 5, 7 contains 10 terms. Note that $ 10 = 3^2 + 1 $. There are four strictly increasing subsequences of length four, namely, 1, 4, 6, 12; 1, 4, 6, 7; 1, 4, 6, 10; and 1, 4, 5, 7. There is also a strictly decreasing subsequence of length four, namely, 11, 9, 6, 5.

Q.8 Solve all questions :

Q8.1

In a Round-Robin tournament, the Tigers beat the Blue Jays, the Tigers beat the Cardinals, the Tigers beat the Orioles, the Blue Jays beat the Cardinals, the Blue Jays beat the Orioles and the Cardinals beat the Orioles. Model this outcome with a directed graph.

Q8.2

Let $ G=(V,E) $ be a simple graph. Let R be the relation on V consisting of pairs of vertices (u, v) such that there is a path from u to v or such that $ u = v $. Show that R is an equivalence relation.

Q8.3

Determine whether the following given pair of directed graphs, shown in Fig. 1 and Fig. 2, are isomorphic or not. Exhibit an isomorphism or provide a rigorous argument that none exists.

Question Diagram

Q.9 Solve all questions :

Q9.1

Use pseudocode to describe an algorithm for determining the value of a game tree when both players follow a minmax strategy.

Q9.2

Suppose that $ T_1 $ and $ T_2 $ are spanning trees of a simple graph G. Moreover, suppose that $ e_1 $ is an edge in $ T_1 $ that is not in $ T_2 $. Show that there is an edge $ e_2 $ in $ T_2 $ that is not in $ T_1 $ such that $ T_1 $ remains a spanning tree if $ e_1 $ is removed from it and $ e_2 $ is added to it, and $ T_2 $ remains a spanning tree if $ e_2 $ is removed from it and $ e_1 $ is added to it.

Q9.3

Show that a degree-constrained spanning tree of a simple graph in which each vertex has degree not exceeding 2 consists of a single Hamiltonian path in the graph.


2019 211405

B.Tech 4th Semester Exam., 2019

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct answer (any seven):

Q1.1

The statement $ p \rightarrow q $ is logically equivalent to

a)

pqp \vee q

b)

pqp \vee \sim q

c)

pq\sim p \vee q

d)

pqp \rightarrow q

Q1.2

The contrapositive of the conditional statement $ p \rightarrow q $ is

a)

qpq \rightarrow p

b)

pq\sim p \rightarrow \sim q

c)

pqp \leftrightarrow q

d)

qp\sim q \rightarrow \sim p

Q1.3

If A and B are two nonempty sets having n elements in common, then $ A \times B $ and $ B \times A $ will have how many elements in common?

a)

2n2^n

b)

n2n^2

c)

n4n^4

d)

2n2n

Q1.4

If a set A have n elements, then how many relations will be there on set A?

a)

n2n^2

b)

2n22^{n^2}

c)

2n2^n

d)

2n2n

Q1.5

If $ P(\phi) $ represents the power set of $ \phi $, then $ n(P(P(P(\phi)))) $ equal to

a)

1

b)

2

c)

3

d)

4

Q1.6

The number of edges in a bipartite graph with n vertices is at most

a)

n22\frac{n^2}{2}

b)

n24\frac{n^2}{4}

c)

n2n^2

d)

2n2n

Q1.7

If $ (S, *) $ is a monoid, where $ S = \{1, 2, 3, 6\} $ is defined by $ a * b = \text{lcm}(a, b) $, and where $ a, b \in S $, then the identity element is

a)

1

b)

2

c)

3

d)

6

Q1.8

The total number of subgroups of a group G of prime order is

a)

1

b)

2

c)

3

d)

4

Q1.9

For the poset $ \{3, 5, 9, 15, 24, 45\} $; divisor of the glb of $ \{3, 5\} $ is

a)

3

b)

5

c)

15

d)

45

Q1.10

The number of pendant vertices of a full-binary tree is

a)

n+12\frac{n+1}{2}

b)

n12\frac{n-1}{2}

c)

2n+12\frac{2n+1}{2}

d)

2n12\frac{2n-1}{2}

Q.2 Solve both questions :

Q2.1

Using truth table, show that-
(i) $ ((p \rightarrow (q \rightarrow r))) \rightarrow ((p \rightarrow q) \rightarrow (p \rightarrow r)) $ is a tautology.
(ii) $ \sim(q \rightarrow r) \wedge r \wedge (p \rightarrow q) $ is a contradiction.

Q2.2

Obtain the principal disjunctive normal form (PDNF) and principal conjunctive normal form (PCNF) of the statement $ (p \rightarrow (q \wedge r)) \wedge (\sim p \rightarrow (\sim q \wedge \sim r)) $.

Q.3 Solve both questions :

Q3.1

For any sets A and B, prove that
(i) $ (A \cup B)' = A' \cap B' $;
(ii) $ (A \cap B)' = A' \cup B' $.

Q3.2

If two sets A and B have n elements in common, then show that the sets $ A \times B $ and $ B \times A $ will have $ 2^n $ elements in common.

Q.4 Solve both questions :

Q4.1

If R is the relation on the set of positive integers, such that $ (a, b) \in R $ if and only if $ a^2 + b $ is even, prove that R is an equivalence relation.

Q4.2

Define partition of a set. If the relation R on the set of integers Z is defined by $ a R b $ iff $ a \cong b \pmod 4 $, find the partition induced by R.

Q.5 Solve both questions :

Q5.1

If R and S be relations on $ A = \{1, 2, 3\} $ represented by the matrices $ M_R = \begin{bmatrix} 1 & 0 & 1 \\ 0 & 1 & 0 \\ 0 & 0 & 0 \end{bmatrix} $ and $ M_S = \begin{bmatrix} 0 & 1 & 1 \\ 1 & 1 & 0 \\ 0 & 0 & 1 \end{bmatrix} $.
Find the matrices that represent (i) $ R \cup S $, (ii) $ R \cap S $, (iii) $ R \circ S $, (iv) $ R - S $, (v) $ R' $, (vi) $ R \circ R $ and (vii) $ R \oplus S $.

Q5.2

Draw the Hasse diagram representing the partial ordering $ \{(A,B) : A \subseteq B\} $ on the power set $ P(S) $ where $ S = \{a,b,c\} $. Find the maximal, minimal, greatest and least elements of the poset.

Q.6 Solve both questions :

Q6.1

Define characteristic function of a set. If A and B are any two subsets of universal set U, then show that:
$ f_{A \cup B}(x) = f_A(x) + f_B(x) - f_{A \cap B}(x) $, for all $ x \in U $

Q6.2

If functions $ f, g, h: Z \rightarrow Z $ are defined as $ f(x) = x-1 $, $ g(x) = 3x $ and $ h(x) = \begin{cases} 0, & \text{if x is even} \\ 1, & \text{if x is odd} \end{cases} $
Verify that $ f \circ (g \circ h) = (f \circ g) \circ h $.

Q.7 Solve both questions :

Q7.1

Show that every group of order 3 is cyclic.

Q7.2

Prove that the necessary and sufficient condition for a non-empty set H of a group (G, *) to be a subgroup is $ a, b \in H \Rightarrow a * b^{-1} \in H $.

Q.8 Solve both questions :

Q8.1

Show that the order of a subgroup of a finite group is a divisor of the order of the group.

Q8.2

Prove that the set S of all real numbers of the form $ a + b\sqrt{2} $ where a, b are integers is an integral domain with respect to usual addition and multiplication.

Q.9 Solve both questions :

Q9.1

Define adjacency matrix and incidence matrix of graph G. Draw the graph represented by the adjacency matrix
$ \begin{bmatrix} 0 & 1 & 1 & 1 \\ 1 & 0 & 1 & 0 \\ 1 & 1 & 0 & 0 \\ 1 & 0 & 0 & 0 \end{bmatrix} $

Q9.2

Show that a tree with n vertices has $ (n-1) $ edges.


2019 V4 211405

B.Tech 4th Semester Exam., 2019

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct answer (any seven):

Q1.1

The statement $ p \rightarrow q $ is logically equivalent to

a)

pqp \vee q

b)

pqp \vee \sim q

c)

pq\sim p \vee q

d)

pqp \rightarrow q

Q1.2

The contrapositive of the conditional statement $ p \rightarrow q $ is

a)

qpq \rightarrow p

b)

pq\sim p \rightarrow \sim q

c)

pqp \leftrightarrow q

d)

qp\sim q \rightarrow \sim p

Q1.3

If A and B are two nonempty sets having n elements in common, then $ A \times B $ and $ B \times A $ will have how many elements in common?

a)

2n2^n

b)

n2n^2

c)

n4n^4

d)

2n2n

Q1.4

If a set A have n elements, then how many relations will be there on set A?

a)

n2n^2

b)

2n22^{n^2}

c)

2n2^n

d)

2n2n

Q1.5

If $ P(\phi) $ represents the power set of $ \phi $, then $ n(P(P(P(\phi)))) $ equal to

a)

1

b)

2

c)

3

d)

4

Q1.6

The number of edges in a bipartite graph with n vertices is at most

a)

n22\frac{n^2}{2}

b)

n24\frac{n^2}{4}

c)

n2n^2

d)

2n2n

Q1.7

If $ (S, *) $ is a monoid, where $ S = \{1, 2, 3, 6\} $ is defined by $ a * b = \text{lcm}(a, b) $, and where $ a, b \in S $, then the identity element is

a)

1

b)

2

c)

3

d)

6

Q1.8

The total number of subgroups of a group G of prime order is

a)

1

b)

2

c)

3

d)

4

Q1.9

For the poset $ \{3, 5, 9, 15, 24, 45\} $; divisor of the glb of $ \{3, 5\} $ is

a)

3

b)

5

c)

15

d)

45

Q1.10

The number of pendant vertices of a full-binary tree is

a)

n+12\frac{n+1}{2}

b)

n12\frac{n-1}{2}

c)

2n+12\frac{2n+1}{2}

d)

2n12\frac{2n-1}{2}

Q.2 Solve both questions :

Q2.1

Using truth table, show that-
(i) $ ((p \rightarrow (q \rightarrow r))) \rightarrow ((p \rightarrow q) \rightarrow (p \rightarrow r)) $ is a tautology.
(ii) $ \sim(q \rightarrow r) \wedge r \wedge (p \rightarrow q) $ is a contradiction.

Q2.2

Obtain the principal disjunctive normal form (PDNF) and principal conjunctive normal form (PCNF) of the statement $ (p \rightarrow (q \wedge r)) \wedge (\sim p \rightarrow (\sim q \wedge \sim r)) $.

Q.3 Solve both questions :

Q3.1

For any sets A and B, prove that
(i) $ (A \cup B)' = A' \cap B' $;
(ii) $ (A \cap B)' = A' \cup B' $.

Q3.2

If two sets A and B have n elements in common, then show that the sets $ A \times B $ and $ B \times A $ will have $ 2^n $ elements in common.

Q.4 Solve both questions :

Q4.1

If R is the relation on the set of positive integers, such that $ (a, b) \in R $ if and only if $ a^2 + b $ is even, prove that R is an equivalence relation.

Q4.2

Define partition of a set. If the relation R on the set of integers Z is defined by $ a R b $ iff $ a \cong b \pmod 4 $, find the partition induced by R.

Q.5 Solve both questions :

Q5.1

If R and S be relations on $ A = \{1, 2, 3\} $ represented by the matrices $ M_R = \begin{bmatrix} 1 & 0 & 1 \\ 0 & 1 & 0 \\ 0 & 0 & 0 \end{bmatrix} $ and $ M_S = \begin{bmatrix} 0 & 1 & 1 \\ 1 & 1 & 0 \\ 0 & 0 & 1 \end{bmatrix} $.
Find the matrices that represent (i) $ R \cup S $, (ii) $ R \cap S $, (iii) $ R \circ S $, (iv) $ R - S $, (v) $ R' $, (vi) $ R \circ R $ and (vii) $ R \oplus S $.

Q5.2

Draw the Hasse diagram representing the partial ordering $ \{(A,B) : A \subseteq B\} $ on the power set $ P(S) $ where $ S = \{a,b,c\} $. Find the maximal, minimal, greatest and least elements of the poset.

Q.6 Solve both questions :

Q6.1

Define characteristic function of a set. If A and B are any two subsets of universal set U, then show that:
$ f_{A \cup B}(x) = f_A(x) + f_B(x) - f_{A \cap B}(x) $, for all $ x \in U $

Q6.2

If functions $ f, g, h: Z \rightarrow Z $ are defined as $ f(x) = x-1 $, $ g(x) = 3x $ and $ h(x) = \begin{cases} 0, & \text{if x is even} \\ 1, & \text{if x is odd} \end{cases} $
Verify that $ f \circ (g \circ h) = (f \circ g) \circ h $.

Q.7 Solve both questions :

Q7.1

Show that every group of order 3 is cyclic.

Q7.2

Prove that the necessary and sufficient condition for a non-empty set H of a group (G, *) to be a subgroup is $ a, b \in H \Rightarrow a * b^{-1} \in H $.

Q.8 Solve both questions :

Q8.1

Show that the order of a subgroup of a finite group is a divisor of the order of the group.

Q8.2

Prove that the set S of all real numbers of the form $ a + b\sqrt{2} $ where a, b are integers is an integral domain with respect to usual addition and multiplication.

Q.9 Solve both questions :

Q9.1

Define adjacency matrix and incidence matrix of graph G. Draw the graph represented by the adjacency matrix
$ \begin{bmatrix} 0 & 1 & 1 & 1 \\ 1 & 0 & 1 & 0 \\ 1 & 1 & 0 & 0 \\ 1 & 0 & 0 & 0 \end{bmatrix} $

Q9.2

Show that a tree with n vertices has $ (n-1) $ edges.


2018 211405

B.Tech 4th Semester Exam., 2018

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct answer (any seven):

Q1.1

For any three sets A, B and C, which of the following statements is wrong?

a)

A(BC)=(AB)CA \cup (B \cup C) = (A \cup B) \cap C

b)

A(BC)=A(BC)A \cup (B \cup C) = A \cup (B \cup C)

c)

A(BC)=(AB)(AC)A \cap (B \cup C) = (A \cap B) \cup (A \cap C)

d)

None of the above

Q1.2

Let A and B be two non-empty sets. Then the set of all ordered pairs (a, b), where $ a \in A $ and $ b \in B $ is called

a)

product set

b)

poset

c)

binary set

d)

None of the above

Q1.3

If $ (a,a) \in R $ or equivalently $ a R a $, $ \forall a \in A $, then a relation R on a set A is called

a)

equivalent

b)

reflexive

c)

symmetric

d)

anti-symmetric

Q1.4

Let A and B be finite sets with $ |A| = n $ and $ |B| = m $. How many functions are possible from A to B with A as the domain?

a)

n

b)

mmm^m

c)

m

d)

mnm^n

Q1.5

For the functions f and g defined by $ f(x) = x^3 $ and $ g(x) = x^2 + 1 \; \forall x \in R $, the value of $ (g \circ f)(x) $ is

a)

x2+1x^2 + 1

b)

x3+1x^3 + 1

c)

x6+1x^6 + 1

d)

x5+1x^5 + 1

Q1.6

A group G is said to be Abelian (or commutative) if for every

a)

a,bGa, b \in G

b)

ab=baa \cdot b = b \cdot a

c)

Both (i) and (ii)

d)

None of the above

Q1.7

If $ f : G \rightarrow G' $ is a homomorphism, then which of the following it true?

a)

f(e)=ef(e) = e

b)

f(e)=ef(e) = e'

c)

f(e) &gt;= \Phi

d)

f(e)=1f(e) = 1

Q1.8

For which of the following does there exist a tree satisfying the specified constraints?

a)

A full binary tree with 31 leaves, each leaf of height 5

b)

A rooted tree of height 3 where every vertex has atmost 3 children and there are 41 total vertices

c)

A full binary tree with 11 vertices and height 6

d)

A binary tree with 2 leaves and height 100

Q1.9

For which of the following does there exist a graph $ G(V, E) $ satisfying the specified conditions?

a)

A tree with 9 vertices and the sum of the degrees of all the vertices is 18

b)

A graph with 5 components, 12 vertices and 7 edges

c)

A graph with 5 components, 30 vertices and 24 edges

d)

A graph with 9 vertices, 9 edges and no cycles

Q1.10

The number of simple digraphs with $ |V| = 3 $ is

a)

292^9

b)

282^8

c)

272^7

d)

262^6

Q.2 Solve both questions :

Q2.1

Let $ f(x) = ax^2 + b $ and $ g(x) = cx^2 + d $, where a, b, c and d are constants. Determine for which constants a, b, c and d the following equation holds: $ f \circ g = g \circ f $

Q2.2

Show that the relation $ (x, y) R (a, b) $ such that $ x^2 + y^2 = a^2 + b^2 $ is an equivalence relation on the plane and describe the equivalence classes.

Q.3 Solve both questions :

Q3.1

Let $ (G, \cdot) $ be a group, where $ \cdot $ is usual multiplication operation on G. Then show that for any $ x, y \in G $ following equations hold:
(i) $ (x^{-1})^{-1} = x $
(ii) $ (xy)^{-1} = y^{-1}x^{-1} $

Q3.2

Construct the truth table for $ [(p \vee q) \wedge (p \rightarrow r) \wedge (q \rightarrow r)] \rightarrow r $. Also show that above statement is a tautology by developing a series of logical equivalences.

Q.4 Solve both questions :

Q4.1

If $ A = \{1, 2, 4\} $, $ B = \{2, 5, 7\} $ and $ C = \{1, 3, 7\} $, find $ (A \times B) \cup (A \times C) $.

Q4.2

List the ordered pairs in the relation R from $ A = \{1, 2, 3, 4\} $ to $ B = \{2, 3, 4, 5\} $, where $ (a, b) \in R $ if and only if-
(i) $ a = b $
(ii) $ a + b = 5 $

Q.5 Solve both questions :

Q5.1

Show that the set of integers with the composition $ \circ $ and * defined by $ a \circ b = a + b + 1 $ and $ a * b = ab + a + b $ is a ring.

Q5.2

State and prove Lagrange's theorem.

Q.6 Solve both questions :

Q6.1

Define a relation R on the set Z of all integers as follows: $ m R n \Leftrightarrow m+n $ is even for all $ m, n \in Z $. Is R a partial order relation? Prove or give a counter example.

Q6.2

Show that the group
(i) $ \{1, 2, 3, 4\}, X_5 $
(ii) $ \{1, 2, 3, 4, 5, 6\}, X_7 $
is cyclic.

Q.7 Solve both questions :

Q7.1

Let $ A = \{0, 1, 2, 3\} $, $ R = \{(x, y) : x+y=3\} $, $ S = \{(x, y) : 3|(x+y)\} $, $ T = \{(x, y) : \max(x,y)=3\} $. Compute (i) $ R \circ T $, (ii) $ T \circ R $ and (iii) $ S \circ S $.

Q7.2

In a group of 70 cars tested by a garage in Delhi, 15 had faulty tyres, 20 had faulty breaks and 18 exceeded the allowable emission limits. Also, 5 cars had faulty tyres and brakes, 6 failed on tyres and emission, 10 failed on brakes and emissions, and 4 cars were unsatisfactory in all three respects. How many cars had no faults in these three checks? Draw an appropriate Venn diagram.

Q.8 Solve both questions :

Q8.1

Define the vertex connectivity and edge connectivity of a graph. Prove that for a graph G with n vertices and e edges, vertex connectivity $ \le $ edge connectivity $ \le 2e/n $.

Q8.2

Define the adjacency matrix of a graph. Find the rank of the regular graph with n vertices and with degree $ p (< n) $ of every vertex.

Q.9 Write short notes on any three of the following:

Q9.1
a)

Multigraphs

b)

Planar graphs

c)

Cosets

d)

Ring polynomials


2018 V2 211405

B.Tech 4th Semester Exam., 2018

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct answer (any seven):

Q1.1

For any three sets A, B and C, which of the following statements is wrong?

a)

A(BC)=(AB)CA \cup (B \cup C) = (A \cup B) \cap C

b)

A(BC)=A(BC)A \cup (B \cup C) = A \cup (B \cup C)

c)

A(BC)=(AB)(AC)A \cap (B \cup C) = (A \cap B) \cup (A \cap C)

d)

None of the above

Q1.2

Let A and B be two non-empty sets. Then the set of all ordered pairs (a, b), where $ a \in A $ and bBb \in B is called

a)

product set

b)

poset

c)

binary set

d)

None of the above

Q1.3

If (a,a)R(a,a) \in R or equivalently aRaa R a, aA\forall a \in A, then a relation R on a set A is called

a)

equivalent

b)

reflexive

c)

symmetric

d)

anti-symmetric

Q1.4

Let A and B be finite sets with A=n|A| = n and B=m|B| = m. How many functions are possible from A to B with A as the domain?

a)

n

b)

mmm^m

c)

m

d)

mnm^n

Q1.5

For the functions f and g defined by f(x)=x3f(x) = x^3 and $ g(x) = x^2 + 1 ; \forall x \in R ,thevalueof, the value of (g \circ f)(x) $ is

a)

x2+1x^2 + 1

b)

x3+1x^3 + 1

c)

x6+1x^6 + 1

d)

x5+1x^5 + 1

Q1.6

A group G is said to be Abelian (or commutative) if for every

a)

a,bGa, b \in G

b)

ab=baa \cdot b = b \cdot a

c)

Both (i) and (ii)

d)

None of the above

Q1.7

If f:GGf : G \rightarrow G' is a homomorphism, then which of the following it true?

a)

f(e)=ef(e) = e

b)

f(e)=ef(e) = e'

c)

f(e) &gt;= \Phi

d)

f(e)=1f(e) = 1

Q1.8

For which of the following does there exist a tree satisfying the specified constraints?

a)

A full binary tree with 31 leaves, each leaf of height 5

b)

A rooted tree of height 3 where every vertex has atmost 3 children and there are 41 total vertices

c)

A full binary tree with 11 vertices and height 6

d)

A binary tree with 2 leaves and height 100

Q1.9

For which of the following does there exist a graph G(V,E)G(V, E) satisfying the specified conditions?

a)

A tree with 9 vertices and the sum of the degrees of all the vertices is 18

b)

A graph with 5 components, 12 vertices and 7 edges

c)

A graph with 5 components, 30 vertices and 24 edges

d)

A graph with 9 vertices, 9 edges and no cycles

Q1.10

The number of simple digraphs with V=3|V| = 3 is

a)

292^9

b)

282^8

c)

272^7

d)

262^6

Q.2 Solve both questions :

Q2.1

Let f(x)=ax2+bf(x) = ax^2 + b and g(x)=cx2+dg(x) = cx^2 + d, where a, b, c and d are constants. Determine for which constants a, b, c and d the following equation holds: fg=gff \circ g = g \circ f

Q2.2

Show that the relation (x,y)R(a,b)(x, y) R (a, b) such that x2+y2=a2+b2x^2 + y^2 = a^2 + b^2 is an equivalence relation on the plane and describe the equivalence classes.

Q.3 Solve both questions :

Q3.1

Let (G,)(G, \cdot) be a group, where \cdot is usual multiplication operation on G. Then show that for any x,yGx, y \in G following equations hold:
(i) $ (x^{-1})^{-1} = x $
(ii) (xy)1=y1x1(xy)^{-1} = y^{-1}x^{-1}

Q3.2

Construct the truth table for $ [(p \vee q) \wedge (p \rightarrow r) \wedge (q \rightarrow r)] \rightarrow r $. Also show that above statement is a tautology by developing a series of logical equivalences.

Q.4 Solve both questions :

Q4.1

If A={1,2,4}A = \{1, 2, 4\}, B={2,5,7}B = \{2, 5, 7\} and C={1,3,7}C = \{1, 3, 7\}, find $ (A \times B) \cup (A \times C) $.

Q4.2

List the ordered pairs in the relation R from A={1,2,3,4}A = \{1, 2, 3, 4\} to $ B = {2, 3, 4, 5} ,where, where (a, b) \in R $ if and only if-
(i) $ a = b $
(ii) a+b=5a + b = 5

Q.5 Solve both questions :

Q5.1

Show that the set of integers with the composition \circ and * defined by $ a \circ b = a + b + 1 andand a * b = ab + a + b $ is a ring.

Q5.2

State and prove Lagrange's theorem.

Q.6 Solve both questions :

Q6.1

Define a relation R on the set Z of all integers as follows: mRnm+nm R n \Leftrightarrow m+n is even for all m,nZm, n \in Z. Is R a partial order relation? Prove or give a counter example.

Q6.2

Show that the group
(i) $ {1, 2, 3, 4}, X_5 $
(ii) $ {1, 2, 3, 4, 5, 6}, X_7 $
is cyclic.

Q.7 Solve both questions :

Q7.1

Let A={0,1,2,3}A = \{0, 1, 2, 3\}, R={(x,y):x+y=3}R = \{(x, y) : x+y=3\}, $ S = {(x, y) : 3|(x+y)} ,, T = {(x, y) : \max(x,y)=3} .Compute(i). Compute (i) R \circ T ,(ii), (ii) T \circ R and(iii)and (iii) S \circ S $.

Q7.2

In a group of 70 cars tested by a garage in Delhi, 15 had faulty tyres, 20 had faulty breaks and 18 exceeded the allowable emission limits. Also, 5 cars had faulty tyres and brakes, 6 failed on tyres and emission, 10 failed on brakes and emissions, and 4 cars were unsatisfactory in all three respects. How many cars had no faults in these three checks? Draw an appropriate Venn diagram.

Q.8 Solve both questions :

Q8.1

Define the vertex connectivity and edge connectivity of a graph. Prove that for a graph G with n vertices and e edges, vertex connectivity \le edge connectivity 2e/n\le 2e/n.

Q8.2

Define the adjacency matrix of a graph. Find the rank of the regular graph with n vertices and with degree p (&lt; n) of every vertex.

Q.9 Write short notes on any three of the following:

Q9.1
  • Multigraphs
  • Planar graphs
  • Cosets
  • Ring polynomials
a)

Multigraphs

b)

Planar graphs

c)

Cosets

d)

Ring polynomials


2016 211405

B.Tech 4th Semester Exam., 2016

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose and write the correct option (any seven):

Q1.1

Let f and g be the functions defined by $ f(x) = 2x+3 $ and $ g(x) = 3x-2 $ then composition of f and g is

a)

6x+66x+6

b)

5x+55x+5

c)

6x+76x+7

d)

7x+57x+5

Q1.2

Among 200 people, 150 either swim or jog or both. If 85 swim and 60 swim and jog, how many jog?

a)

125

b)

225

c)

85

d)

25

Q1.3

A graph in which all nodes are of equal degree is known as graph.

a)

complete

b)

multi-

c)

non-regular

d)

regular

Q1.4

The minimum number of spanning trees in a connected graph with n nodes is

a)

n1n-1

b)

n/2n/2

c)

2

d)

1

Q1.5

If a set contains exactly m distinct elements where m denotes some non-negative integer, then the set is

a)

finite

b)

infinite

c)

None of the above

d)

All of the above

Q1.6

In an unweighted, undirected-connected graph, the shortest path from a node S to every other node is computed most efficiently, in terms of time complexity, by

a)

Dijkstra's algorithm starting from S

b)

Warshall's algorithm

c)

performing a DFS starting from S

d)

performing a BFS starting from S

Q1.7

The negation of 'Today is Friday' is

a)

Today is Saturday

b)

Today is not Friday

c)

Today is Thursday

d)

Today is Sunday

Q1.8

Whether the relation R on the set of all integers is reflexive, symmetric, anti-symmetric, or transitive, where $ (x, y) \in R $ if and only if $ xy \ge 1 $?

a)

Anti-symmetric

b)

Transitive

c)

Symmetric

d)

Both symmetric and transitive

Q1.9

If $ p = \text{'It is raining'} $ and $ q = \text{'She will go to college'} $, 'It is raining and she will not go to college' will be denoted by

a)

pqp \rightarrow \sim q

b)

pqp \wedge q

c)

pq\sim p \wedge q

d)

(pq)\sim(p \wedge q)

Q1.10

If $ x > 0 $ and $ x^2 < 0 $, then $ x \ge 10 $.

a)

True

b)

False

c)

Both (i) and (ii)

d)

None of the above

Q.2 Solve both questions :

Q2.1

Define the following terms and give an example for each:
Reflexive relation, irreflexive relation, antisymmetric relation, partition set

Q2.2

Prove that, if $ S = \{s_1, s_2, \cdots, s_k\} $ be a set, then $ P(S) $ has $ 2^k $ elements.

Q.3 Solve this question :

Q3.1

Define 'group', 'order of a group', and 'Abelian group'. Prove that every subgroup of a cyclic group is cyclic.

Q.4 Solve both questions :

Q4.1

Define the following with example:
Ring, homomorphism, cyclic group, coset

Q4.2

Determine whether f is one-one or onto for the following cases:
(i) Let $ A = B = \{1, 2, 3, 4\} $ and $ f = \{(1, 1), (2, 3), (4, 2)\} $
(ii) Let $ A = \{a, b, c\} $, $ B = \{1, 2, 3, 4\} $ and $ f = \{(a, 1), (b, 1), (c, 4)\} $

Q.5 Solve both questions :

Q5.1

Suppose H and K are normal subgroups of G with $ H \cap K = \{1\} $. Show that $ xy = yx $ for all $ x \in H $ and $ y \in K $. Let $ I \in R $ be an ideal.

Q5.2

The radical $ \sqrt{I} = \{r \in R | rn \in I, n \in N\} $. Show that $ \sqrt{I} $ is an ideal.

Q.6 Solve both questions :

Q6.1

State and prove De Morgan's laws of set theory.

Q6.2

In a survey of 260 college students, the following data were obtained: 64 had taken a mathematics course, 94 had taken a computer science course, 58 had taken a business course, 28 had taken both a mathematics and a business course, 26 had taken both a mathematics and a computer science course, 22 had taken both a computer science and a business course, and 14 had taken all three types of courses.
(i) How many of these students had taken none of the three courses?
(ii) How many had taken only a computer science course?

Q.7 Solve both questions :

Q7.1

Prove that for any non-empty binary tree T, if $ n_0 $ is the number of leaves and $ n_2 $ be the number of nodes having degree two, then $ n_0 = n_2 + 1 $.

Q7.2

Derive total number of nodes of a binary tree having depth n.

Q.8 Solve all questions :

Q8.1

What is graph? Differentiate between directed and undirected graph.

Q8.2

How many different ways can you represent a graph? Explain each of the representations by examples. What is complete graph?

Q8.3

Prove that the sum of degrees of all vertices in a graph is always even.

Q.9 Solve both questions :

Q9.1

Consider the graph given below:
(a) Find the adjacency list and BFS traversal of the above graph.

Prove that the maximum number of edges possible in a simple graph of n nodes is $ n(n-1)/2 $.

Question Diagram

2016 V4 211405

B.Tech 4th Semester Exam., 2016

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose and write the correct option (any seven):

Q1.1

Let f and g be the functions defined by $ f(x) = 2x+3 $ and $ g(x) = 3x-2 $ then composition of f and g is

a)

6x+66x+6

b)

5x+55x+5

c)

6x+76x+7

d)

7x+57x+5

Q1.2

Among 200 people, 150 either swim or jog or both. If 85 swim and 60 swim and jog, how many jog?

a)

125

b)

225

c)

85

d)

25

Q1.3

A graph in which all nodes are of equal degree is known as graph.

a)

complete

b)

multi-

c)

non-regular

d)

regular

Q1.4

The minimum number of spanning trees in a connected graph with n nodes is

a)

n1n-1

b)

n/2n/2

c)

2

d)

1

Q1.5

If a set contains exactly m distinct elements where m denotes some non-negative integer, then the set is

a)

finite

b)

infinite

c)

None of the above

d)

All of the above

Q1.6

In an unweighted, undirected-connected graph, the shortest path from a node S to every other node is computed most efficiently, in terms of time complexity, by

a)

Dijkstra's algorithm starting from S

b)

Warshall's algorithm

c)

performing a DFS starting from S

d)

performing a BFS starting from S

Q1.7

The negation of 'Today is Friday' is

a)

Today is Saturday

b)

Today is not Friday

c)

Today is Thursday

d)

Today is Sunday

Q1.8

Whether the relation R on the set of all integers is reflexive, symmetric, anti-symmetric, or transitive, where $ (x, y) \in R $ if and only if $ xy \ge 1 $?

a)

Anti-symmetric

b)

Transitive

c)

Symmetric

d)

Both symmetric and transitive

Q1.9

If $ p = \text{'It is raining'} $ and $ q = \text{'She will go to college'} $, 'It is raining and she will not go to college' will be denoted by

a)

pqp \rightarrow \sim q

b)

pqp \wedge q

c)

pq\sim p \wedge q

d)

(pq)\sim(p \wedge q)

Q1.10

If $ x > 0 $ and $ x^2 < 0 $, then $ x \ge 10 $.

a)

True

b)

False

c)

Both (i) and (ii)

d)

None of the above

Q.2 Solve both questions :

Q2.1

Define the following terms and give an example for each:
Reflexive relation, irreflexive relation, antisymmetric relation, partition set

Q2.2

Prove that, if $ S = \{s_1, s_2, \cdots, s_k\} $ be a set, then $ P(S) $ has $ 2^k $ elements.

Q.3 Solve this question :

Q3.1

Define 'group', 'order of a group', and 'Abelian group'. Prove that every subgroup of a cyclic group is cyclic.

Q.4 Solve both questions :

Q4.1

Define the following with example:
Ring, homomorphism, cyclic group, coset

Q4.2

Determine whether f is one-one or onto for the following cases:
(i) Let $ A = B = \{1, 2, 3, 4\} $ and $ f = \{(1, 1), (2, 3), (4, 2)\} $
(ii) Let $ A = \{a, b, c\} $, $ B = \{1, 2, 3, 4\} $ and $ f = \{(a, 1), (b, 1), (c, 4)\} $

Q.5 Solve both questions :

Q5.1

Suppose H and K are normal subgroups of G with $ H \cap K = \{1\} $. Show that $ xy = yx $ for all $ x \in H $ and $ y \in K $. Let $ I \in R $ be an ideal.

Q5.2

The radical $ \sqrt{I} = \{r \in R | rn \in I, n \in N\} $. Show that $ \sqrt{I} $ is an ideal.

Q.6 Solve both questions :

Q6.1

State and prove De Morgan's laws of set theory.

Q6.2

In a survey of 260 college students, the following data were obtained: 64 had taken a mathematics course, 94 had taken a computer science course, 58 had taken a business course, 28 had taken both a mathematics and a business course, 26 had taken both a mathematics and a computer science course, 22 had taken both a computer science and a business course, and 14 had taken all three types of courses.
(i) How many of these students had taken none of the three courses?
(ii) How many had taken only a computer science course?

Q.7 Solve both questions :

Q7.1

Prove that for any non-empty binary tree T, if $ n_0 $ is the number of leaves and $ n_2 $ be the number of nodes having degree two, then $ n_0 = n_2 + 1 $.

Q7.2

Derive total number of nodes of a binary tree having depth n.

Q.8 Solve all questions :

Q8.1

What is graph? Differentiate between directed and undirected graph.

Q8.2

How many different ways can you represent a graph? Explain each of the representations by examples. What is complete graph?

Q8.3

Prove that the sum of degrees of all vertices in a graph is always even.

Q.9 Solve both questions :

Q9.1

Consider the graph given below:
(a) Find the adjacency list and BFS traversal of the above graph.

Prove that the maximum number of edges possible in a simple graph of n nodes is $ n(n-1)/2 $.

Question Diagram

2015 211405

B.Tech 4th Semester Exam., 2015

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct option (any seven):

Q1.1

The set of all real numbers under the usual multiplication operation is not a group since

a)

multiplication is not a binary operation

b)

multiplication is not associative

c)

identity element does not exist

d)

zero has no inverse

Q1.2

If $ R = \{(1, 2), (2, 3), (3, 3)\} $ be a relation defined on $ A = \{1, 2, 3\} $, then $ R \circ R $ is

a)

R itself

b)

{(1,2),(1,3),(3,3)}\{(1, 2), (1, 3), (3, 3)\}

c)

{(1,3),(2,3),(3,3)}\{(1, 3), (2, 3), (3, 3)\}

d)

{(2,1),(1,3),(2,3)}\{(2, 1), (1, 3), (2, 3)\}

Q1.3

Pick out the correct statement(s):

a)

The set of all 2×22 \times 2 matrices with rational entries (with the usual operations of matrix addition and matrix multiplication) is a ring which has no nontrivial ideals.

b)

Let R=C[0,1]R = C[0,1] be considered as a ring with the usual operations of pointwise addition and pointwise multiplication and let $ I = {f : [0,1] \rightarrow R | f(1/2) = 0} $. Then I is a maximal ideal.

c)

Let R be a commutative ring and let P be a prime ideal of R. Then R/P is an integral domain.

d)

None of the above is correct

Q1.4

Let f and g be the functions defined by $ f(x) = 2x+3 $ and $ g(x) = 3x+2 $. Then the composition of f and g is

a)

6x+66x+6

b)

5x+55x+5

c)

6x+76x+7

d)

7x+57x+5

Q1.5

Among 200 people, 150 either swim or jog or both. If 85 swim and 60 swim and jog, then how many people jog?

a)

125

b)

225

c)

85

d)

25

Q1.6

If a graph is a tree, then

a)

it has 2 spanning trees

b)

it has only 1 spanning tree

c)

it has 4 spanning trees

d)

it has 5 spanning trees

Q1.7

The relation R on the set of all integers, where $ (x, y) \in R $ if and only if $ xy \ge 1 $ is

a)

anti-symmetric

b)

transitive

c)

symmetric

d)

both transitive and symmetric

Q1.8

How many functions are there from a set with three elements to a set with two elements?

a)

6

b)

8

c)

12

d)

7

Q1.9

Which one of the following is correct for any simple connected undirected graph with more than 2 vertices?

a)

No two vertices have the same degree

b)

At least two vertices have the same degree

c)

At least three vertices have the same degree

d)

All vertices have the same degree

Q1.10

In an unweighted, undirected connected graph, the shortest path from a node S to every other node is computed most efficiently, in terms of time complexity, by

a)

Dijkstra's algorithm starting from S

b)

Warshall's algorithm

c)

performing a DFS starting from S

d)

performing a BFS starting from S

Q.2 Solve this question :

Q2.1

Define set. Let X be the universal set and $ S \subset X $, $ T \subset X $. Then prove that:
(a) $ (S \cup T)^c = S^c \cap T^c $
(b) $ (S \cap T)^c = S^c \cup T^c $

Q.3 Solve both questions :

Q3.1

Define relations and function. What is equivalence relation?

Q3.2

Let A be the set of all people in India. If $ x, y \in A $, then let us say that $ (x,y) \in R $ if x and y have the same surname (i.e., last name). Then prove that R is an equivalence relation.

Q.4 Solve this question :

Q4.1

Define group, Abelian group and groupoid. Also define composition of functions. Let $ f: R \rightarrow \{x \in R: x \ge 0\} $ be given by $ f(x) = x^4 + x^2 + 6 $ and $ g: \{x \in R: x \ge 0\} \rightarrow R $ be given by $ g(x) = \sqrt{x} - 4 $. Then find $ (g \circ f)(x) $ and $ (f \circ g)(x) $.

Q.5 Solve both questions :

Q5.1

Suppose H and K are normal subgroups of G with $ H \cap K = \{1\} $. Show that $ xy = yx $ for all $ x \in H $ and $ y \in K $. Let $ I \in R $ be an ideal.

Q5.2

The radical $ \sqrt{I} = \{r \in R | rn \in I, n \in N\} $. Show that $ \sqrt{I} $ is an ideal.

Q.6 Solve this question :

Q6.1

Define commutative ring. Consider the set X, its power set $ P(X) = \{A | A \subset X\} $ is the set of all subsets of X. Show that the power set is a commutative ring under the following two operations $ A + B = (A - B) \cup (B - A) $ where $ \cup $ is set union and $ - $ is set difference, and $ AB = A \cap B $.

Q.7 Solve this question :

Q7.1

Prove that (a) the maximum number of nodes N on level i of a binary tree is $ 2^i $, $ i \ge 0 $ and (b) the maximum number of nodes in a binary tree of height h is $ 2^h - 1 $, $ h \ge 1 $.

Q.8 Solve this question :

Q8.1

Define Walks, Paths and Circuits related to a graph. Write down all possible (a) paths from $ v_1 $ to $ v_8 $, (b) circuits of G and (c) trails of length three in G from $ v_3 $ to $ v_5 $ of the graph shown in the figure below.

Question Diagram

Q.9 Solve this question :

Q9.1

Show that if a and b are the only two odd degree vertices of a graph G, then a and b are connected in G. Prove that a connected graph G remains connected after removing an edge e from G if and only if e lie in some circuit in G.


2015 V4 211405

B.Tech 4th Semester Exam., 2015

Time 03 Hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Q.1 Choose the correct option (any seven):

Q1.1

The set of all real numbers under the usual multiplication operation is not a group since

a)

multiplication is not a binary operation

b)

multiplication is not associative

c)

identity element does not exist

d)

zero has no inverse

Q1.2

If $ R = \{(1, 2), (2, 3), (3, 3)\} $ be a relation defined on $ A = \{1, 2, 3\} $, then $ R \circ R $ is

a)

R itself

b)

{(1,2),(1,3),(3,3)}\{(1, 2), (1, 3), (3, 3)\}

c)

{(1,3),(2,3),(3,3)}\{(1, 3), (2, 3), (3, 3)\}

d)

{(2,1),(1,3),(2,3)}\{(2, 1), (1, 3), (2, 3)\}

Q1.3

Pick out the correct statement(s):

a)

The set of all 2×22 \times 2 matrices with rational entries (with the usual operations of matrix addition and matrix multiplication) is a ring which has no nontrivial ideals.

b)

Let R=C[0,1]R = C[0,1] be considered as a ring with the usual operations of pointwise addition and pointwise multiplication and let $ I = {f : [0,1] \rightarrow R | f(1/2) = 0} $. Then I is a maximal ideal.

c)

Let R be a commutative ring and let P be a prime ideal of R. Then R/P is an integral domain.

d)

None of the above is correct

Q1.4

Let f and g be the functions defined by $ f(x) = 2x+3 $ and $ g(x) = 3x+2 $. Then the composition of f and g is

a)

6x+66x+6

b)

5x+55x+5

c)

6x+76x+7

d)

7x+57x+5

Q1.5

Among 200 people, 150 either swim or jog or both. If 85 swim and 60 swim and jog, then how many people jog?

a)

125

b)

225

c)

85

d)

25

Q1.6

If a graph is a tree, then

a)

it has 2 spanning trees

b)

it has only 1 spanning tree

c)

it has 4 spanning trees

d)

it has 5 spanning trees

Q1.7

The relation R on the set of all integers, where $ (x, y) \in R $ if and only if $ xy \ge 1 $ is

a)

anti-symmetric

b)

transitive

c)

symmetric

d)

both transitive and symmetric

Q1.8

How many functions are there from a set with three elements to a set with two elements?

a)

6

b)

8

c)

12

d)

7

Q1.9

Which one of the following is correct for any simple connected undirected graph with more than 2 vertices?

a)

No two vertices have the same degree

b)

At least two vertices have the same degree

c)

At least three vertices have the same degree

d)

All vertices have the same degree

Q1.10

In an unweighted, undirected connected graph, the shortest path from a node S to every other node is computed most efficiently, in terms of time complexity, by

a)

Dijkstra's algorithm starting from S

b)

Warshall's algorithm

c)

performing a DFS starting from S

d)

performing a BFS starting from S

Q.2 Solve this question :

Q2.1

Define set. Let X be the universal set and $ S \subset X $, $ T \subset X $. Then prove that:
(a) $ (S \cup T)^c = S^c \cap T^c $
(b) $ (S \cap T)^c = S^c \cup T^c $

Q.3 Solve both questions :

Q3.1

Define relations and function. What is equivalence relation?

Q3.2

Let A be the set of all people in India. If $ x, y \in A $, then let us say that $ (x,y) \in R $ if x and y have the same surname (i.e., last name). Then prove that R is an equivalence relation.

Q.4 Solve this question :

Q4.1

Define group, Abelian group and groupoid. Also define composition of functions. Let $ f: R \rightarrow \{x \in R: x \ge 0\} $ be given by $ f(x) = x^4 + x^2 + 6 $ and $ g: \{x \in R: x \ge 0\} \rightarrow R $ be given by $ g(x) = \sqrt{x} - 4 $. Then find $ (g \circ f)(x) $ and $ (f \circ g)(x) $.

Q.5 Solve both questions :

Q5.1

Suppose H and K are normal subgroups of G with $ H \cap K = \{1\} $. Show that $ xy = yx $ for all $ x \in H $ and $ y \in K $. Let $ I \in R $ be an ideal.

Q5.2

The radical $ \sqrt{I} = \{r \in R | rn \in I, n \in N\} $. Show that $ \sqrt{I} $ is an ideal.

Q.6 Solve this question :

Q6.1

Define commutative ring. Consider the set X, its power set $ P(X) = \{A | A \subset X\} $ is the set of all subsets of X. Show that the power set is a commutative ring under the following two operations $ A + B = (A - B) \cup (B - A) $ where $ \cup $ is set union and $ - $ is set difference, and $ AB = A \cap B $.

Q.7 Solve this question :

Q7.1

Prove that (a) the maximum number of nodes N on level i of a binary tree is $ 2^i $, $ i \ge 0 $ and (b) the maximum number of nodes in a binary tree of height h is $ 2^h - 1 $, $ h \ge 1 $.

Q.8 Solve this question :

Q8.1

Define Walks, Paths and Circuits related to a graph. Write down all possible (a) paths from $ v_1 $ to $ v_8 $, (b) circuits of G and (c) trails of length three in G from $ v_3 $ to $ v_5 $ of the graph shown in the figure below.

Question Diagram

Q.9 Solve this question :

Q9.1

Show that if a and b are the only two odd degree vertices of a graph G, then a and b are connected in G. Prove that a connected graph G remains connected after removing an edge e from G if and only if e lie in some circuit in G.


2014 211405

B.Tech Examination, 2014

Time 3 hours
Full Marks 70
Instructions:
  • The marks are indicated in the right-hand margin.
  • There are NINE questions in this paper.
  • Attempt FIVE questions in all.
  • Question No. 1 is compulsory.

Questions

Q1

Answer the following:

a)

Choose the correct alternative from the following (any seven):

[14 Marks]
Q2

Answer the following:

Q3

Answer the following:

Q4

Answer the following:

Q5

Answer the following:

Q6

Answer the following:

Q7

Answer the following:

Q8

Answer the following:

[14 Marks]
Q9

Answer the following:


2012 105217

B.Tech Examination, 2012

Time 3 hours
Full Marks 70
Instructions:
  • The marks are indicated in right-hand margin.
  • There are TEN questions in this paper.
  • Attempt any FIVE questions.

Questions

Q1

Answer the following:

Q2

Answer the following:

Q3

Answer the following:

Q4

Answer the following:

Q5

Answer the following:

Q6

Answer the following:

Q7

Answer the following:

Q8

Answer the following:

Q9

Answer the following:

[14 Marks]
Q10

Answer the following:

[14 Marks]

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