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Dear all readers. It is Praveen Chhikara. Here is a JAM Mathematics mock test, prepared
according to the exams conducted in the last 3-4 years. Due to lack of time, I could not arrange
the questions them section-wise. A key has been prepared is okay, although I prepared it very
speedily. I hope, it is likely to help you a lot.
Pr
avee
n Chh
ikara
JAM Mathematics Mock Test
Date: Jan 27, 2019 -by Praveen Chhikara ..
1. The greatest value of α for which the power series∑
[2−(−1)n
3]nxn con-
verges for |x| < α, is ............
2. For A ⊆ R, which of the following statements is FALSE?
(a) The closure A of A is equal to the intersection of all closed setswhich contain A.
(b) The interior Ao of A is equal to the union of all open sets whichare contained in A.
(c) Ao = (Ac)c.
(d) (A)o = (Ao).
3. Which of the following series is(are) convergent?
(a)∑∞
n=11+2+3+...+n
2n.
(b) 1 + 12
+ 16
+ 112
+ 136
+ 172
+ . . ..
(c)∑∞
n=1π+tan−1 nn√n+n+1
.
(d)∑∞
n=1
(−1)n sin( 7nπ5
)
n7π3
.
4. Let A,B ⊆ R be nonempty sets.Define d(A,B) = inf{|x − y| : x ∈ A, y ∈ B}. Pick out the validstatement.
(a) If A and B are closed sets with A ∩B = ∅, then d(A,B) > 0.
(b) If A and B are closed sets with d(A,B) = 0, then A ∩B 6= ∅.(c) If A is closed and B is compact, where A ∩B = ∅,
then, d(A,B) = 0 MAY happen.
(d) If A is closed and B is compact, where A∩B = ∅, then, d(A,B) >0.
5. The supremum of the set { ex−e−xex+e−x
: x ∈ R} is ............
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6. The limit of the sequence { 1n
sin(log(n) + 72π)} is ..............
7. Let A ⊆ R be a nonempty set. Which of the following is a WRONGstatement?
(a) If A is a closed set, and (xn) is a Cauchy sequence in A, then (xn)must converge in A.
(b) If (xn) is a Cauchy sequence in N, then (xn) must be eventuallyconstant.
(c) If (xn) is a sequence in A such that (xn) → x, the x may not bean element of A′.
(d) If A is not a closed set, then there exists a sequence (xn) in A suchthat (xn)→ x, where x /∈ A.
8. The series∑ (−1)n
n!is
(a) not convergent.
(b) absolutely convergent.
(c) conditionally convergent.
(d) not absolutely convergent.
9. The set of all limit points of the set {n+ 12n
: n ∈ N} is
(a) N.
(b) N ∪ { 12n
: n ∈ N}.(c) the empty set ∅.(d) { 1
2n: n ∈ N}.
10. Which of the following set is not connected ?
(a) (0, 1].
(b) {x ∈ R : x2 ∈ (0, 1)}.(c) {x ∈ R : cosx < 2}.(d) {x ∈ R : 0 < 1
x< 2}.
11. The surface area of the portion of the paraboloid z = 1 + x2 + y2 thatlies below the plane z = 5 is
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(a)∫ π0
∫ 1
0
√(4r2 + 1).rdrdθ.
(b)∫ 2π
0
∫ 1
0
√(4r2 + 1).rdrdθ.
(c)∫ π0
∫ 2
0
√(4r2 + 1).rdrdθ.
(d)∫ 2π
0
∫ 2
0
√(4r2 + 1).rdrdθ.
12. Let S be the portion of circle (x − a)2 + (y − a)2 = a2 in the firstquadrant. Then
∫∫S
dxdy√(2a−x)
equals
(a) 43
√2a3/2.
(b) 83
√2a3/2.
(c) 23
√2a3/2.
(d)√23a3/2.
13. The limit lim(x,y,x)→(0,0,0)xyz
(x2+y2+z2)1/2is equal to ............
14. Consider the function
f(x, y) =
x sin( 1
x) + y sin( 1
y) if x 6= 0, y 6= 0
x sin( 1x) if x 6= 0, y = 0
y sin( 1y) if x = 0, y 6= 0
0 if x = 0, y = 0.
Then
(a) the partial derivatives of f exist at (0, 0).
(b) the function f is continuous at (0, 0).
(c) the function f is differentiable at (0, 0).
(d) the function f is not differentiable at (0, 0).
15. The volume of the solid that is below the surface z = 3x+ 2y over theregion R on the plane z = 0 bounded by the curves x = 0, y = 0 andx+ 2y = 4 is
(a) 325
.
(b) 645
.
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(c) 643
.
(d) 323
.
16. Suppose f(x, y) = 2x3 + 6xy2 − 3y3 − 150x. Then
(a) (5, 0) is a point of local maximum.
(b) (3, 4) is neither a point of local maximum nor of local minimum.
(c) (−5, 0) is neither a point of local maximum nor of local minimum.
(d) (−3,−4) is a point of local minimum.
17.The smallest subgroup of (a) containing a6 and a12 is(a) (a3).(b) (a48).(c) (a6).(d) (a24).18. Which of the following is(are) true ?(a) R∗ has no proper subgroup of finite index.(b) R∗ has exactly one proper subgroup of finite index.(c) C∗ has no proper subgroup of finite index.(d) C∗ has exactly one proper subgroup of finite index.19.Which of the following statements is true?(a) There exists a group homomorphism from Z24 onto Z6 ⊕ Z2.(b) There does not exist a group homomorphism from Z28 onto Z6.(c) There does not exist a group homomorphism from Z24 onto Z8.(d) There exists a group homomorphism φ : Z36 → Z20 such thatφ(1) = 2.20.The set of all n× n real orthogonal matrices with determinant 1 formsa group wrt matrix multiplication, denoted by SO(n,R) Which of thefollowing is true ?(a) SO(2,R) is isomorphic to {z ∈ C : |z| = 1}.(b) SO(2,R) is not isomorphic to {z ∈ C : |z| = 1}.(c) SO(2,R) is not isomorphic to the group of all rotations of the planeabout the origin.(d) SO(2,R) is not isomorphic to R/Z.
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21The number of the elements of order 5 in S7 equals .............22
Let G be the group with 101 elements. Suppose a belongs to G. Thenumber of solutions of x2 = a in G is equal to ...............23The last two digits of 131010 are .........24Suppose S is the part of cylinder z = 1 − x2, 0 ≤ x ≤ 1,−2 ≤ y ≤ 2
and, C is the boundary curve of the surface S and if−→F = yi+ yj + zk,
then |∮C
−→F .dR| equals......
25.Let S be the sphere x2 + y2 + z2 = 4 and,
−→F = 7xi − zk. Then
|∫ ∫
S=−→F .d−→S | equals
(a) 32π(b) 64π(c) 128π(d) 16π .26.Suppose S is the portion of the plane 2x − 2y + z = 1 lying in the
first octant. The flux∫ ∫
S
−→F .d−→S through S, where the normal points
upwards, is(a) 1/2.(b) 1/4.(c) 1/6.(d) 1/8.27.Consider the vector field
−→F = (2x cos y−2z3)i+(3+2yez−x2 sin y)j+
(y2ez − 6xz2)k. Then
(a) there does not exist a function f(x, y, z) such that−→F = 5f .
(b) if C1 and C2 are any two smooth curves from (1, 0, 1) to (0, 1, 0),
then∫C1
−→F .d−→r =
∫C2
−→F .d−→r .
(c) curl−→F = 0.
(d) if C is any closed smooth curve , then∮c
−→F .d−→r must be zero.
28.If the value of
∮c−y3dx+xy2dy
(x2+y2)2, where C is the ellipse x2 + 4y2 = 4, is nπ,
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then n is equal to ..............29.For the function f(x, y) = x2y , if the gradient5f at (3, 2) is (m,n),then m+ n is equal to ,,,,,,,,,,,30.Assuming continuity of all partial derivatives involved, which of thefollowing is FALSE?(a) curl grad r4 = 0.(b) div(5ϕ×5ψ) = 0.(c) curl(ϕ grad ϕ) 6= 0.
(d) div curl−→F = 0.
31.Which of the following statements is true ?(a) If A is an n× n matrix over R, then the dimension ofspan{I, A,A2...} is equal to n.(b) There exists a 5 × 5 matrix A over R such that the vector spaceM5(R) of all 5× 5 matrices over R is spanned by {I, A,A2..., A25}.(c) If A is a 5 × 5 real symmetric matrix with eigenvalues 1, 1, 1, 1, 1,then the dimension of span{I, A,A2...} is 5.(d) If A is a 5 × 5 real symmetric matrix with eigenvalue 1, 1, 1, 1, 1,then the dimension of span{I, A,A2...} is 1.32.If the system
x− 3y + 2z = 5
2x− 5y − 3z = 9
−x− y + kz = 0
has a unique solution, then k is anything other than ..........33.Let V be the vector space of all continuous functions over [0, 1]. Sup-pose T : V −→ V is a linear transformation defined by T (f(x)) =∫ 1
0f(t) sin(x− t)dt, for all f ∈ V , and for all x ∈ [0, 1]. Then
(a) the nullspace of T is the zero space.
(b) the nullspace of T is {f ∈ V :∫ 1
0f(t) cos(t)dt =
∫ 1
0f(t) sin(t)dt =
0}(c) the rangespace of T is V itself.(d) the rangespace of T is span {sinx, cosx}.34.
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Let T : R2 → R3 be a linear transformation such that T (1, 1) =(2, 1, 8), T (0,−1) = (1, 1,−5). The matrix representation of T wrt thestandard bases is
(a)
1 13 −12 5
.(b)
1 12 53 −1
.(c)
1 12 −13 5
.(d)noneofthese.
35.The dimension of the smallest subspace of R4 that contains (1, 2, 5, 1), (1, 0,−1, 2),(0, 2, 6,−1) and (1, 2, 5, 1) is .............36.Let A be a 6 × 6 matrix of rank 5 such that det(A − ωI) 6= 0, for
ω = e±2πi
3 . The rank of A2 + A+ I is ..............37.Suppose α, β, γ are the distinct roots of x3 = 1 , then the value of
∣∣∣∣∣∣α β γβ γ αγ α β
∣∣∣∣∣∣ is ...............
38.Consider the matrix
A =
1 5 −75 2 4−7 4 −3
.Then(a) there exists no nonsingular matrix P such that P−1AP is a diagonal
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matrix.(b) there exists a nonsingular matrix P such that P−1AP is a diagonal matrix.(c) there exist more than one nonsingular matrices P such that P−1AP is adiagonal matrix.(d) there exists an orthogonal matrix P such that P−1AP is a diagonalmatrix.39.Let V be the vector space of all sequences {an} in F which has only a finitelymany nonzero terms an wrt. the operations {an + bn} = {an} + {bn} and{can} = c{an} for c ∈ F. If S spans V , then(a) S may be finite.(b) S is uncountable.(c) S is at least countable infinite.(d) none of the above can be concluded.40.Suppose V is a 2-dimensional space, and T : V → V is a linear operator suchthat T 2 = 0, but T 6= 0. If v ∈ V such that Tv 6= 0 , then {v, Tv}(a) is linearly dependent(b) spans V(c) is not a basis for V(d) does not span V . 41.Consider f : R→ R defined by
f(x) = x2 − 2x, x ∈ Q,
f(x) = 3x− 6, x ∈ Qc.
(a) The function is continuous at x = 2.(b) The function is differentiable at x = 2.(c) The function is continuous at x = 3.(d) The function is differentiable at x = 3.42.Let f : R→ R be a monotone function. Then f(a) has at most finitely many discontinuities.(b) has at most countable infinitely many discontinuities.(c) may have uncountable number of discontinuities.(d) none of these.43.
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Which of the following statements is true ?(a) There exists a continuous function from [0, 1] onto R.(b) There does not exist a continuous function from R onto (0, 1).(c) There exists a continuous function f : R→ R which takes on every valuethrice.(d) There exists a continuous function f : R→ R which takes on every valueexactly twice.44.The limit limx→0
−2ln(cosx)x2
is equal to ...............45.Which of the following is always true ?(a) If f(x) and g(x) are continuous at x = a, then f(x)
g(x)is continuous at x = a.
(b) If f(x) + g(x) is continuous at x = a and f′(a) = 0, then g(x) is contin-
uous at x = a.(c) If f(x) + g(x) is differentiable at x = a, then f(x) and g(x) are bothdifferentiable at x = a.(d) There exist functions f(x) and g(x) such that f(x), f(x) + g(x) are bothcontinuous at x = a, but g(x) is discontinuous at x = a.46.Let f(x) =
∫ x0et sin tdt . The function increases in
(a) (0, π2).
(b) (0, 2π).(c) (−π
2, 0).
(d) (−2π, 0).47.The number of the values of x where the function f(x) = cos x + cos(
√2x)
attains its maximum is(a) 0.(b) 1.(c) 2.(d) infinitely many.48.Let f be a continuously differentiable function defined on the interval [0, 3]and assume that f(0) = 1, f(1) = 2 and f(3) = 2. Then(a) There exists a point c ∈ [0, 3] such that f(c) = c.(b) There exists a point c ∈ [0, 3] such that f
′(c) = 1/3.
(c) There exists a point c ∈ [0, 3] such that f′(c) = 1.
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(b) There exists a point c ∈ [0, 3] such that f′(c) = 1/4.
49.If [.] represents the greatest integer function, then
∫ 3
0[x]dx is equal to ............
50.The function f(x) = |x| + |x + 1| + |x + 2| is not differentiable at n points,where n is.................51.Consider the function f : [0, 1]→ R, defined by limm→∞limn→∞[1+cos2m(n!πx)].Then(a) f is only continuous at rational points.(b) f is only continuous at irrational points.(c) f is continuous in [0, 1].(d) f is discontinuous everywhere.52.The coefficient of x3 in the Taylor series expansion of f(x) =
√1 + x about
the point a = 0 is α16
, where α is .............
53.An integrating factor of (3xy + y2)dx+ (x2 + xy)dy = 0 is(a) x.(b) x2.(c) x3.(d) x4.54.The initial-value problem y
′=√y, y(0) = 0 has
(a) no solution.(b) a unique solution.(c) countably infinite solutions.(d) uncountably many solutions.55.Suppose a, b, c > 0 and λ ≥ 0. The solutions of ay
′+ by = ce−λx
(a) tend to 0 as x→∞ ,if λ = 0.(b) tend to c
bas x→∞ ,if λ = 0.
(c) tend to 0 as x→∞ ,if λ > 0.(d) tend to c
bas x→∞ ,if λ > 0.
56.Consider the initial-problem y
′+ 2y = f(x), where f(x) = 1 if 0 ≤ x ≤ 1,
and f(x) = 0 if 1 < x ≤ 2, y(0) = 0. Then f(3/2) equals
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(a) 1e2
sinh(1).(b) 1
e2cosh(1).
(c) 1e
sinh(1).(d) 1
ecosh(1).
57.The general solution of x2y
′′ − 2xy′+ 2y = 0, x < 0
(a) C1x+ C2x2.
(b) C1x− C2x2.
(c) −C1x+ C2x2.
(d) −C1x− C2x2.
58.The value of n for which each member of the family y = xn
6+ c intersects the
hyperbola xy = 2 orthogonally is .............59.Consider the differential equation y
′′+ 2y
′+ 5y = f(x), x ≥ 0 where f :
[0,∞)→ R is a bounded and continuous function.(a) There exists an unbounded solution of the given differential equation.(b) Each solution of the given differential equation is bounded(c) There exists a discontinuous solution of the given differential equation(d) Each solution of the given differential equation is continuous.60.If the solution y(x) of the initial-value problem y
′′+ 2y
′+ 5y = 0, y(0) =
0, y′(0) = 2 at x = 1 is enx sin(mx), then m+ n is............
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