CSIR NET Maths previous year question papers

Single choice · The Real Line

1. A

   S is empty.

2. B

   There is a bijection between S and $\mathbb{N}$

3. C

   There is a bijection between S and $\mathbb{R}$

4. D

   There is a bijection between S and a non-empty finite set

Single choice · The Real Line

1. A

   There exists a non-empty finite set in C

2. B

   There exists a countably infinite set in C

3. C

   There exists an uncountable set in C

4. D

   C is empty

Single choice · The Real Line

1. A

   if $liminf_{n}\to\infty a_{n} = limsup_{n}\to\infty a_{n}$, then $(a_{n})$ is convergent

2. B

   if inf{$a_{n}$ | n ≥ 1} $= limsup_{n}\to\infty a_{n}$, then $(a_{n})$ is convergent

3. C

   if sup{$a_{n}$ | n ≥ 1} $= liminf_{n}\to\infty a_{n}$, then $(a_{n})$ is constant

4. D

   if sup{$a_{n}$ | n ≥ 1} = inf{$a_{n}$ | n ≥ 1}, then $(a_{n})$ is constant

Single choice · Continuity and Differentiation

1. A

   0

2. B

   1

3. C

   Countably infinite

4. D

   Uncountable

Single choice · Continuity and Differentiation

1. A

   If f is continuous on the set S, then f is continuous on the set $\mathbb{R}$ \ S

2. B

   If g is continuous, then f is continuous on the set S

3. C

   If g is identically 0 and f is continuous on the set $\mathbb{R}$ \ S, then f is identically 0

4. D

   If g is identically 0 and f is continuous on the set S, then f is identically 0

Single choice · Sequences and Series of Functions

1. A

   There exists $x \in \mathbb{R}$ such that f(x) is not defined

2. B

   f(x) = 0 for all $x \in \mathbb{R}$

3. C

   f(x) = x for all $x \in \mathbb{R}$

4. D

   f(x) = |x| for all $x \in \mathbb{R}$

Single choice · Vector Spaces and Linear Maps

1. A

   If A is one-to-one but not onto, then m > n

2. B

   If A is onto but not one-to-one, then m < n

3. C

   If A is bijective, then m = n

4. D

   If A is one-to-one, then m = n

Single choice · Vector Spaces and Linear Maps

1. A

   There exists a vector $v \in \mathbb{R}^{10}$ such that Av ≠ 0 and $A^{2}v = 0$

2. B

   There exists a vector $v \in \mathbb{R}^{10}$ such that $A^{2}v \ne 0$

3. C

   A must have a non-zero eigenvalue

4. D

   $A^{7} = 0$

Single choice · Eigenvalues and Canonical Forms

1. A

   24 − ab = 4c

2. B

   a + b = 8

3. C

   c = 6

4. D

   ab = 0

Single choice · Vector Spaces and Linear Maps

1. A

   (x − 2)(x − 1)

2. B

   $x^{2}(x - 2)(x - 1)$

3. C

   $(x - 2)^{2}(x - 1)^{2}$

4. D

   $(x^{2} - 2)(x^{2} - 1)$

Single choice · Inner Product Spaces and Forms

1. A

   A is invertible

2. B

   There exist non-zero vectors v, w such that ⟨v, w⟩ = 0

3. C

   ⟨u, v⟩ ≠ ⟨u, w⟩ for all non-zero vectors u, v, w with v ≠ w

4. D

   Every eigenvalue of $A^{2}$ is positive

Single choice · Inner Product Spaces and Forms

1. A

   $x^{2} + 2y^{2} + 3z^{2}$

2. B

   $x^{2} + 2y^{2} + 3z^{2} - 2$xy

3. C

   $x^{2} + 2y^{2} + 3z^{2} - 2$xy − 2yz

4. D

   $x^{2} + 2y^{2} - 3z^{2}$

Multi-select · full marks only for the exact set · The Real Line

1. A

   {$x \in \mathbb{R}$ | [x] = 1}

2. B

   {$x \in \mathbb{R}$ | x − [x] = 1/2}

3. C

   {$x \in \mathbb{R}$ | $x \ge 0, \sqrt{x} \in \mathbb{Q}$}

4. D

   {$x \in \mathbb{R}$ | $x^{2} \in \mathbb{Q}$}

Multi-select · full marks only for the exact set · The Real Line

1. A

   sup A is finite.

2. B

   $\lim \sup(n\to\infty) 1/(\sqrt{n + \sqrt{n}} - \sqrt{n}) < \sup A$

3. C

   $\lim \inf(n\to\infty) 1/(\sqrt{n + \sqrt{n}} - \sqrt{n}) = 2$

4. D

   $\lim \sup(n\to\infty) 1/(\sqrt{n + \sqrt{n}} - \sqrt{n}) = 3$

Multi-select · full marks only for the exact set · Continuity and Differentiation

1. A

   S is empty.

2. B

   S is non-empty.

3. C

   f must be uniformly continuous.

4. D

   f need not be uniformly continuous.

Multi-select · full marks only for the exact set · Sequences and Series of Functions

1. A

   $(g_{n})_{n}\ge_{1}$ converges uniformly on any compact subset of $\mathbb{R}$ but not on $\mathbb{R}$.

2. B

   $(g_{n})_{n}\ge_{1}$ converges uniformly on $\mathbb{R}$.

3. C

   There exists a subsequence of $(h_{n})_{n}\ge_{1}$ that converges uniformly on $\mathbb{R}$.

4. D

   For every compact subset $K \subseteq \mathbb{R}$, there exists a subsequence of $(h_{n})_{n}\ge_{1}$ that converges uniformly on K.

Multi-select · full marks only for the exact set · Sequences and Series of Functions

1. A

   $(x^{n}g(x))_{n}\ge_{1}$ converges uniformly on [0, 1].

2. B

   $(x^{n}g(x))_{n}\ge_{1}$ does not converge uniformly on [0, 1].

3. C

   $(x^{n}h(x))_{n}\ge_{1}$ converges uniformly on [0, 1].

4. D

   $(x^{n}h(x))_{n}\ge_{1}$ does not converge uniformly on [0, 1].

Multi-select · full marks only for the exact set · Eigenvalues and Canonical Forms

1. A

   The set {$I, A, \dots, A^{n}$} is linearly independent but the set {$I, A, \dots, A^(n^{2})$} is not linearly independent.

2. B

   If A is a singular matrix, then the set {I, A, …, A^k} spans a (k + 1)-dimensional subspace of V for all k ≤ rank(A).

3. C

   The sets {$I, A, \dots, A^{n}$} and {$I, A, \dots, A^(n^{2})$} both span the same subspace of V.

4. D

   The set {$I, A, \dots, A^{n}$} is linearly dependent.

Multi-select · full marks only for the exact set · Eigenvalues and Canonical Forms

1. A

   $\varphi$ is one-to-one but not onto.

2. B

   $\varphi$ is onto but not one-to-one.

3. C

   There exists $f \in \mathbb{R}[x]$ such that deg f ≤ n and $\ker \varphi =$ {fg | $g \in \mathbb{R}[x]$}.

4. D

   deg h ≥ n for every nonzero $h \in \ker \varphi$.

Multi-select · full marks only for the exact set · Eigenvalues and Canonical Forms

1. A

   The characteristic polynomial of T can be $x^{2} + x + 1$.

2. B

   The characteristic polynomial of T can be x(x − 1).

3. C

   The minimal polynomial of T can be $x^{2}$.

4. D

   The characteristic polynomial of T can be $x(x - e^(2\pi{}i/3))$.

Multi-select · full marks only for the exact set · Eigenvalues and Canonical Forms

1. A

   There exists a nonzero $v \in \mathbb{R}^{4}$ such that $q_{1}(T)v = 0$.

2. B

   There exists a nonzero $v \in \mathbb{R}^{4}$ such that $q_{1}(T)v = 0$ and $q_{2}(T)v = 0$.

3. C

   For all nonzero $v \in \mathbb{R}^{4}, v$ and Tv are linearly independent.

4. D

   If $q_{1}(T)v = 0$ for some nonzero $v \in \mathbb{R}^{4}$, then {v, Tv, $T^{2}v, T^{3}v$} is a basis of $\mathbb{R}^{4}$.

Multi-select · full marks only for the exact set · Inner Product Spaces and Forms

1. A

   The set {$v_{1}, v_{2}$} is linearly independent.

2. B

   If $c_{1} \ne c_{2}$, then ⟨$v_{1}, v_{2}$⟩ = 0.

3. C

   If $c_{1} = c_{2}$, then $c_{3} = c_{2}$.

4. D

   If $c_{1} \ne c_{2}$, then $c_{3} = c_{2}$.

Multi-select · full marks only for the exact set · Inner Product Spaces and Forms

1. A

   $f(v_{2}, v_{1}) = -s$.

2. B

   If r = s = t, then either f(v, v) ≥ 0 for all v ∈ V or f(v, v) ≤ 0 for all v ∈ V.

3. C

   If f is positive definite, then r ≠ s, s ≠ t and r ≠ t.

4. D

   If f is positive definite, then $f(v_{1}, v_{2}) = 0$.

Multi-select · full marks only for the exact set · Metric Spaces

1. A

   d_X is a metric on X which induces the topology $\tau$.

2. B

   The topological space $(X, \tau)$ is connected.

3. C

   $(P_{n})_{n}\ge_{1}$ converges to $P_{0}$ in the topological space $(X, \tau)$.

4. D

   The topological space $(X, \tau)$ is compact.

Multi-select · full marks only for the exact set · Integration

1. A

   F is Riemann integrable.

2. B

   If F(x) = 0 for all x ∈ [0, 1], then f(x) = 0 for all x ∈ [0, 1].

3. C

   F is uniformly continuous on [0, 1].

4. D

   F is differentiable on (0, 1).