Explore topic-wise InterviewSolutions in Current Affairs.

This section includes 7 InterviewSolutions, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

1.

Examine the continuity of the function f(x) = {(|x-a| sin ((1)/(x-a))",","if " x ne a),(0",","if' x = a):} at x=a

Answer»


ANSWER :x=a
2.

What are the coordinates of a point which is common to all the coordinate planes.

Answer»

SOLUTION :ORIGIN O(0,0,0) is COMMON to all COORDINATE PLANES.
3.

Let p, q be real numbers. If alphais the root ofx^(2) +3p^(2)x+5q^(2)=0, betais a root of x^(2) + 9p^(2)x + 15q^(2) = 0 and 0 lt alpha lt beta, then the equationx^(2) +6p^(2)x +10q^(2)=0has a root gammathat always satisfies

Answer»

`GAMMA =ALPHA//4 +BETA`
`beta LT gamma`
`gamma = alpha//2 +beta`
`alpha lt gammalt beta`

ANSWER :d
4.

If f(x)=((a^(x)-1)^(3))/(sin (x log a)log (1+x^(2) log a^(2)) is continuous at x=0 , then f(0)=

Answer»

LOG a
2 log a
`log a^(-1)`
`log sqrta`

ANSWER :D
5.

intdx/(sqrtx-root(3)(x))(x=t^6)

Answer»

SOLUTION :`INTDX/(sqrtx-root(3)(x))` [Put`x=t^6
`dx=6t^5`]
=`(6t^2dt)/(t^3-t^2)=6int(t^3dt)/(t-1)=6int((t^3-1)+1)/(t-1)DT`
=`6int{t^2+t+1+1/(t-1)}dt`
=`6{1/3 t^3+1/2 t^2+t+Inabs(t-1)}+C`
=`2sqrtx+3root(3)(x)+6x^(1/6)+6Inabs(x^(1/6)-1)+C`
6.

Findthecoordinatesofthepointofintersection for the following lines :( x-3 ) /(1) = (y-5 ) /( 2 )=(z- 1 ) /(- 1)and( x-4 ) /(2) =(y- 2 ) /( - 1)=(z -4 ) /(2)

Answer»


ANSWER :`( 2, 3, 2 ) `
7.

If ((1-3x)^(1//2)+(1-x)^(5//3))/(sqrt(4-x)) is approximately equal to a+bx for small values of x, then (a,b)=

Answer»

`(1,(35)/(24))`
`(1,-(35)/(24))`
`(2,(35)/(12))`
`(2,-(35)/(12))`

Solution :`(b)` `((1-3x)^(1//2)+(1-x)^(5//3))/(2[1-(x)/(4)]^(1//2))`
`=([1+(1)/(2)(-3x)]+[1+(5)/(3)(-x)])/(2[1+(1)/(2)(-(x)/(4))])`
(Neglecting HIGHER POWERS of `x`)
`=([1-(19)/(12)x])/([1-(x)/(8)])`
`=[1-(19)/(12)x][1-(x)/(8)]^(-1)`
`=[1-(19)/(12)x][1+(x)/(8)]=1-(35)/(24)x`
then `a+bx=1-(35)/(24)ximpliesa=1`, `b=-(35)/(24)`
8.

int_(4)^(5) e^(x) dx.

Answer»


ANSWER :`E^(4)(e-1)`
9.

The solution of (dy)/(dx)+ (xy)/(1 + x^(2)) = (1)/(x (1 + x^(2))) is

Answer»

`ysqrt(1+x^(2)) = sec^(-1)x+c`
`ysqrt(1+x^(2)) = -"cosec" H^(-1) x+c`
`ysqrt(1+x^(2)) = sin^(-1)x+c`
`ysqrt(1-x^(2)) = Tan^(-1)x+c`

Answer :B
10.

If f has a local extremum at a and if f'(a) exists then

Answer»

`F'(a) LT 0`
`f'(a) GT 0`
`f'(a) = 0`
`f''(a) = 0`

Answer :C
11.

If p is the point of contact of thecircles x^2 + y^2 + 4x + 4y - 10 = 0and x^2 + y^2 - 6x - 6y + 10 = 0and Q is theirexternal centre of similitude, then the equation of the circle with P and Q as the extremities of its diameter is

Answer»

`x^2 + y^2 + 14X + 14y - 26 = 0`
`x^2 + y^2 + 5x + 5y - 8 = 0`
`x^2 + y^2 - 5x - 5y + 8 = 0`
`x^2 + y^2 - 14x - 14y + 26 = 0`

Answer :D
12.

Minimize z=sum_(j=1)^(n)""sum_(i=1)^(m)c_("ij ")x_("ij") Subject to : sum_(j=1)^(n)x_("ij")=a_(i),i=1,..........,m sum_(i=1)^(n)x_("ij")=b_(i),j=1,..........,n is a LPP with number of constraints

Answer»

m + N
`m - n `
MN
`(m)/(n)`

ANSWER :A
13.

A common tangent tox^(2)-2y^(2)=18and x^(2)+ y^(2) =9 is

Answer»

` y =2x + 3SQRT5`
` y= SQRT2 x +3SQRT3 `
` y= 2x +3sqrt7 `
` y= sqrt2x +3sqrt5`

ANSWER :B
14.

A realvalued functionf (x)satisfiesthe functionalequationf (x-y)= f(x) f(y) - f(a-x)f(a +y)wherea isa givenconstantand f (0)=1,f(2a -x)isequalto

Answer»

`F(X)`
`-f(x)`
`f(-x)`
`f(a) +f(a-x)`

ANSWER :B
15.

The probability that an event A occurs in a single trial of an experiment is 0.6. Three independent trials of the experiment are performed. Find the probability that the event at least once occurs.

Answer»

SOLUTION :P (event at LEAST once)
`=1-[1-0.6]^3`
=1-0.064
=0.936
16.

If A is an invertible matrix of order 2, then det(A^(-1)) is equal to

Answer»

DET (A)
`(1)/( det(A))`
`1`
`0`

ANSWER :B
17.

Find the least and the greatest value of 2sin x + sin 2x over [0, 2pi].

Answer»

`3SQRT3`
3
`(3sqrt(3))/2`
2

Answer :C
18.

If 0 lt y lt 2^(1//3) and x(y^(3)-1)=1 then (2)/(x)+(2)/(3x^(3))+(2)/(5x^(5))+…….oo

Answer»

`LOG((y^(3))/(2-y^(3)))`
`log((y^(3))/(1-y^(3)))`
`log((2Y^(3))/(1-y^(3)))`
`log((y^(3))/(1-2y^(3)))`

ANSWER :A
19.

int_(e)^(2) d^(x) dx as a limit of sum:

Answer»


ANSWER :`E^(2)-1`
20.

the point lies in half plane x-2y

Answer»

(5,2)
(3,1)
(4,1)
(-1,0)

ANSWER :D
21.

How many 10 letter words can be formed using 26 English letters such that each word must include A, B but separated exactly with 3 letters.

Answer»


ANSWER :`12XX"^(24)P_8`
22.

Which among the following is/are true ? I. The values of cosec x repeat after an interval of 2pi. II. The values of sec x repeat after an interval of 2pi. III. The values of cot x repeat after an interval of pi.

Answer»

I is TRUE
II is true
III is true
All are true

ANSWER :D
23.

Compute the magnitude of the following vectors : a = hat(i)+hat(j)+hat(k),b=2hat(i)-7hat(j)-3hat(k),c=(1)/(sqrt(3))hat(i)+(1)/(sqrt(3))hat(j)-(1)/(sqrt(3))hat(k).

Answer»


ANSWER :`|veca|=sqrt(3),|vecb|=sqrt(62),|vecc|=1`
24.

Integration by partial fraction : int(x^(2)+x-1)/(x^(2)+x-6)dx=....

Answer»

`x+LOG(x+3)+log(x-2)+C`
`x-log(x+3)+log(x-2)+c`
`x-log(x+3)-log(x-2)+c`
NONE of these

Answer :B
25.

Find the centre and radius of each of the circles whose equations are given below. 2x^(2) + 2y^(2) - 3x + 2y - 1 =0

Answer»


ANSWER :` ((3)/(4) , (-1)/(2)) , (sqrt21)/(4)`
26.

cos^(-1)((-1)/2)-2 sin^(-1)(1/2)+3 cos^(-1) ((-1)/sqrt2) -4 tan^(-1) (-1) equals

Answer»

`(19pi)/12`
`(35pi)/12`
`(47pi)/12`
`(43pi)/12`

ANSWER :D
27.

The value of determinant |(a-b ,b+c,a),(b-a,c+a,b),(c-a,a+b,c)| is

Answer»

1.`a^(3)+B^(3)+C^(3)`
2.3ABC
3.`a^(3)+b^(3)+c^(3)-3abc`
4.`a^(3)+b^(3)+c^(3)+3abc`

28.

Find the rate at which the volume of a spherical balloon will increase when its radius is 2 meters if the rate of increase of its redius is 0.3 m/min.

Answer»

Solution :Let r be the radius of a spherical ballon.
Give that dr/dt = 0.3 m/min.
If V be the volume of the ballon then `dV/dt = 3/4 PI r _3`.
`rArr Dv/dt = 3/4 pi cdot 3r^2 dr/dt = 4 pi r^2 dr/dt`
`therefore Dv/dt](r=2) = 4pi xx4 XX cdot 3 = 4 cdot 8 pi m^3/min`
`therefore` The volume increase at the rate of `4 cdot 8 pi m^3/min`.
29.

Form the differential equation of all circles touching the x-axis at the origin and center on y-axis.

Answer»


Answer :`(DY)/(DX) = (2xy)/(X^(2) - y^(2))`
30.

int_(0)^(b) (dx)/(1+x^2)= int_(b)^(oo) (dx)/(1+x^2), then b is equal to

Answer»

`TAN^(-1) ((1)/(3))`
`(sqrt3)/(2)`
`sqrt2`
1

Answer :D
31.

If y = (cos x - sin x)/( cos x + sin x ) , "then " (dy)/(dx)

Answer»

`X^(2)`
`y^(2)`
`1 + y^(2)`
`- (1 + y^(2))`

ANSWER :D
32.

Ifx^4 - 12x ^3 +52 x^2 - 96x+64=0havepairsof equalrootsthen therootsare

Answer»

`1,1,5,5`
`2,2,4,4`
`3,3,3,3`
`-5,-1,-5,-1`

ANSWER :B
33.

If a number x is selected from natural numbers 1 to 100 find the prbability for x + (100)/(x) gt 29.

Answer»


ANSWER :`(39)/(50)`
34.

The position vector of the point P is (4, 5, -3). The distance of the point P from the plane XY, YZ and XZ is P_(1),P_(2) and P_(3) respectively then underset(i=1)overset(3)sumP_(i)=………..

Answer»

6
12
`2sqrt(25)`
`5sqrt(2)`

ANSWER :B
35.

If the equations of two circles whose radii are a and a' are S=0 and S'=0 , then show that the circles S/a+(S')/(a')=0 and S/a-(S')/(a')=0 intersect orthogonally.

Answer»

`(pi )/(3) `
` ( pi)/(4) `
`( pi )/(2) `
` (pi )/(6)`

ANSWER :C
36.

Arrange the following angles in ascending order (A) Angle between the vectors I + 3j + 4k and I - 3j + 2k (B) Angle between the planes r. (2i - j + k) = 7 and r. (I + j + 2k) = 11 (C ) Angle between the lines r = x(I + 2j + 2k) and r = t(3i + 2j + 6k)

Answer»

A,B,C
C,B,A
B,C,A
B,A,C

Answer :B
37.

find the general solution of sec^(2)xtan y dx + sec^(2) y tan x dy = 0

Answer»


ANSWER :`TAN X tan y = C`
38.

Find the slope of the tangent to the curve y=x^(3)-3x+2 at the point whose x - coordinate is 3.

Answer»


ANSWER :24
39.

If veca and vecb are unit vectors such that [veca, vecb, veca xx vecb]=(1)/(4), then the angle between veca and vecb is :

Answer»

`(PI)/(6)`
`(pi)/(4)`
`(pi)/(3)`
`(pi)/(2)`

SOLUTION :N/A
40.

Internal bisectors of DeltaABC meet the circumcircle at point D, E, and F Length of side eF is

Answer»

`2R cos.(A)/(2)`
`2R SIN ((A)/(2))`
`R cos((A)/(2))`
`2R cos((B)/(2)) cos((C)/(2))`

Solution :Area of `DeltaABC = (abc)/(4R) = 2R^(2) sin A sin B sin C`
`angleADE = angleABE = (B)/(2)`
SIMILARLY, `angleFDA = angleFCA = (C)/(2)`
`rArr angleFDE = (B+C)/(2)`
and `angleDEF = (A+C)/(2) and angleDFE = (A +B)/(2)`

In `DeltaDEF`, by SINE rule, `(EF)/(sin (angleFDE)) = 2R`
`rArr EF = 2R cos ((A)/(2))`
Then, area of `DeltaDEF`
`= 2R^(2) sin ((A+B)/(2)) sin ((B+C)/(2)) sin ((A+C)/(2))`
`=2R^(2) cos ((A)/(2)) cos ((B)/(2)) cos ((C)/(2))`
Now `(Delta_(ABC))/(Delta_(DEF)) = (2R^(2) sin A sin B sin C)/(2R^(2) cos ((A)/(2)) cos((B)/(2)) cos((C)/(2)))`
`= 8sin ((A)/(2)) sin ((B)/(2)) sin ((C)/(2)) le 1`
`rArr Delta_(ABC) le Delta_(DEF)`
41.

Evaluate underset(-pi//2)overset(pi/2)int sin|x| dx

Answer»

0
1
2
4

Answer :C
42.

(i) If 'a' is a complex number such that |a| = 1. Find the values of a, so that equation az^2 + z+1=0 has one purely imaginary root. (ii) Show that ((pi+1)/(pi-1))^(m) e^(2mi cot^(-1) (p))=1.

Answer»


ANSWER :`COS^(-1) ((sqrt5-1)/(2))`
43.

If( 1+ x ) ^n= C _ 0+ C _ 1x+C_ 2x ^ 2+ … + C_n x ^ n, thenC _0+2 C_1+ 3C_2+ … + (n + 1 ) C_ nisequal to

Answer»

`2^N+n.2^(n -1) `
`2^(n-1)+ n.2^n`
` 2 ^n + (n+ 1 ) 2 ^n`
` 2 ^(n - 1 )+ (n-1 ) 2 ^n `

Solution : ` ( 1 + x ) ^n = C _0 + C _ 1x +C _ 2x ^ 2+ … +C_n x ^ n `
` RARRX ( 1 + x ) ^n= C _0x+ C _ 1x ^ 2+C _ 2x ^3+… +C_n x ^ ( n+ 1 ) `
Differentiatingonbothsides
`XN (1 +x) ^(n - 1 )+(1 + x ) ^n= C_0+2C_1 x+3 C_2x ^ 2+... ( n + 1 ) C _ n x ^ n `
Substituting`x= 1`inaboveequation,
`thereforen ( 2 )^(n - 1 )+2^n=C_0+2C_1+ 3 C_2+... +(n + 1 )C_ n `
44.

The straight line y=2x meets y=f(x) at P, where f(x) is a solution of the differential equation (dy)/(dx)=(x^(2)+xy)/(x^(2)+y^(2)) such that f(1)=3, then f'(x) at point P is

Answer»

`(3)/(5)`
`(5)/(3)`
2
1

Answer :A
45.

If A,B,C,D are the length of normals to the curves 1) y=4x^2 at (-1,4) 2) y=x^3+1 at (1,2)3) y=(x^3)/(2-x) at (1,1) 4) 2x^2+3xy-2y^2=8 at (2,3)then the ascending order of A,B,C,D is

Answer»

A,B,C,D
B,C,D,A
A,B,D,C
C,B,D,A

Answer :D
46.

a circles S of radius 'a' is the director circle of another circleS_(1).S_(2) is the director circle of S_(2) and so on. If the sum of radius of S, S_(1), S_(2), S_(3) …. circlesis '2' and a=(k-sqrt(k)), then the value of k is ……

Answer»


ANSWER :2
47.

Let E = 1^(2017) + 2^(2017) + 3^(2017) + ... + 2016^(2017), then E is divisible by

Answer»

2016
2017
4033
`2016^(2)`

ANSWER :B
48.

Find lambda if the vectors hati-hatj+hatk, 3hati-hatj+2hatk and hati+lambda hatj-3hatk are coplannar.

Answer»


ANSWER :`LAMBDA =15`
49.

For a biased die the probability for different faces to turn up are given below. {:("Face",1,2,3,4,5,6),("Probability",0.1,0.32,0.21,0.15,0.05,0.17):} The die is tossed and you are told either face 1 or 2 has turned up. Then the probability that it is face 1 is

Answer»

`5//21`
`6//23`
`5//23`
`16//21`

ANSWER :A
50.

Express A= [{:(3,5),(1,-1):}] as sun of symmetric and skew symmetric matrix.

Answer»


ANSWER :(i) `A=[(3,3),(3,-1)]+[(0,2),(-2,0)]`
(ii) `A=[(6,-2,2),(-2,3,-1),(2,-1,3)]+[(0,0,0),(0,0,0),(0,0,0)]`
(iii) `A=[(3,(1)/(2),(-5)/(2)),((1)/(2),-2,-2),((-5)/(2),-2,2)]+[(0,(5)/(2),(3)/(2)),((-5)/(2),0,3),((-3)/(2),-3,0)] (IV)A=[(1,2),(2,2)]+[(0,3),(-3,0)]`