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.

If the tangents and normals at the extremities of a focal chord of a parabola intersect at (x_(1),y_(1)) and (x_(2),y_(2)) respctively then

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`x_(1)=x_(2)`
`x_(1)=y_(2)`
`y_(1)=y_(2)`
`x_(2)=y_(1)`

ANSWER :C
2.

int dx/(sin x + sin 2x )=

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`1/2 log_(e) abs(1+ COS x ) + 1/6 log_(e) abs(1-cosx) -2/3 log_(e) abs(1+ 2cos x ) + c`
`1/2 log_(e) abs(1+ cos x ) -2/3 log_(e) abs(1-cosx) +1/2 log_(e) abs(1+ 2cos x ) + c`
`1/2 log_(e) abs(1+ SIN x ) -1/3 log_(e) abs(1-sinx) -1/3 log_(e) abs(1+ cos x ) + c`
`1/2 log_(e) abs(1- sin x ) +1/2 log_(e) abs(1+cosx) -2/3 log_(e) abs(1- 2cos x ) + c`

ANSWER :A
3.

The solution of (dy)/(dx) = (x-2y + 3)/(2x-y + 5) is

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`X^(2) - 4xy +y^(2) + 6x - 10 y = C`
`x^(2) - 4xy + y^(2) + 6x + 10 y = c`
`x^(2) + 4xy + y^(2) + 6x - 10 y = c`
`x^(2) - 4xy - y^(2) - 6x - 10 y = c`

Answer :A
4.

then

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F(x) attains itsminimum at x=0
f(x) attains its MAXIMUM at x=0
f'(x) =0 at morethanthree points in `(-pi , pi)`
f(x) =0 atexactly three points in `(-pi, pi)`

ANSWER :B::C
5.

If the line passing through P=(8,3) meets the circle S-=x^(2)+y^(2)-8x-10y+26=0 at A,B then PA.PB=

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5
10
15
25

Answer :A
6.

Find the second order derivatives of the functions x^(2) + 3x+ 2

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ANSWER :2
7.

Find the derivative of the function given by f(x) = (1 + x) (1 + x^(2)) (1 + x^(4)) (1 + x^(8)) and hence find f'(1)

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ANSWER :120
8.

Let a_(0)x^(n)+a_(1)x^(n-1)+…+a_(n-1)x+a_(n)=0 be the degree equation with a_(0),a_(1),…a_(n) integers. If p/q is a rational root of theis equation, then p is a divisor of a_(n) and q is a divisor of a_(0). If a_(0)=1, then every rational root of thsi equation must be an integer. At least one integral root of the equation x^(3)-13x^(2)+15x+189=0 exceeds another root by

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1
2
3
none of these

Answer :B
9.

Find the area of the region {(x, y) : y^(2) le 4x, 4x^(2) + 4y^(2) le 9}

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ANSWER :`(9pi)/(8)-9/4 SIN^(-1) (1/3) +1/(3sqrt2)`
10.

find the generalsolution : (dy)/(dx)= sin x

Answer»
11.

For all real values of a _(0) , a _(1), a _(2), a _(3) satisfying a _(0)+ (a _(1))/(2) + (a _(2))/( 3) + ( a _(3))/(4) =0, the equationa _(0) + a _(1) x + a _(2) x ^(2) + a _(3) x ^(3) =0has a real root in the interval

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`[0,1]
`[-1, 0]`
`[1,2]`
`[-2,-1]`

ANSWER :A
12.

If f(x)={:{(3x^2+12"," x-1),(37-x ","2 lt x le 3):} then

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f(X) INCREASING on [-1,2]
f(x) is continuos on [-1,3]
f(2) does not exist
all of these

Solution :`underset(xrarr2^-)limf(x)=underset(xrarr2^+)limf(x)=f(2)`
So f(x) is CONTINUOUS on [-1,3] THUS options (b) and (c ) are correct .
ALSO
`(LHD at x =2) ={d/(dx)(37 -x)}_(atx=2)`=24
Clearly f(x) is not differentiableat x=2
So f(2) does not exist.
Now `f(x)={(6x+12","-1 lt xlt 2 ),(-1","2 ltx lt 3):}`
Cleary `f' (x)lt 0 for all x in [-1, 2] `
So f(x) in increasing on [-1,2]
Thus option (a) is correct .
13.

The parabola x^2=4ay makes an intercept of length sqrt40 units on the line y=1+2x then a values of 4a is

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A2
B-2
C-1
D4

Answer :B
14.

Evalute the following integrals int (1)/(sqrt(1 + x - x^(2)) dx

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ANSWER :`SIN^(-1)((2x-1)/(sqrt(5)))+C`
15.

{:(" "Lt),(n rarr oo):} sum_(r=1)^(n)((r^(3))/(r^(4)+n^(4)))=

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LOG 2
`1/2 log 2`
`1/3 log 2`
`1/4 log 2`

ANSWER :D
16.

The matrix A =((p,-q),(q,p)) is orthogonal if and only if

Answer»

<P>`p^(2)+q^(2)=1`
`p^(2)=q^(2)`
`p^(2)=q^(2)+1`
NONE of these

Answer :A
17.

From a lot of 30 bulbs which include 6 defectives, a sample of 4 bulbs is drawn at random with replacement. Find the probability distribution of the number of defective bulbs.

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ANSWER :`(##NCERT_TAM_MAT_XII_P2_C13_E04_006_A01##)`
18.

if 1,log_(9)(3^(1 - x) + 2),log_(3)[4.3^(x) - 1] are in A.P. then x equals

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`log_(3)4`
`1 - log_(3)4`
`1 - log_(4)3`
`log_(4)3`

Answer :C
19.

If a plane P passes through the points (1, 0, 0), (0, 1, 0) and makes an angle pi/4 with the plane x+y=3, then the direction ratios of a normal to that plane P is

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`1, SQRT(2), 1`
`1, 1, sqrt(2)`
`1, 1, 2`
`sqrt(2), 1, 1`

ANSWER :B
20.

The number of ways in which we can choose two positive integers from 1 to 100 such that their product is a multiple of 3 is

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`""^(100)C_(2)-""^(33)C_(2)`
`""^(100)C_(2)-""^(67)C_(2)`
`""^(33)C_(2)`
`""^(100)C_(2)`

Answer :B
21.

A pair of fair dice is rolled 2 times. Find the mean of the number of doublets on the dice. Find also variance of the number of doublets on the dice.

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ANSWER :`(1)/(3), (5)/(18)`
22.

ABCD is a parallelogram with vec(AC) = hati - 2hatj + hatk and vec(BD) = -hati + 2hatj - 5hatk. Area of this parallelogram is equal to:

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`sqrt(5)//2` sq. UNITS
`2sqrt(5)` sq. units
`4sqrt(5)` sq. units
`sqrt(5)` sq. units

ANSWER :B
23.

If a variable takes values 0, 1, 2,…,n with frequencies q^(n), (n)/(1)q^(n-1)p, (n(n-1))/(1.2)q^(n-2)p^(2),…,p^(n) where p+q = 1, then the mean is

Answer»

pq
NP
nq
`np^(2)`

ANSWER :B
24.

Prove that cot((pi)/8) - tan((pi)/8) = 2

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SOLUTION :`COT(pi/8)-TAN(pi/8)=1/(tan(pi/8))-tan(pi/8)/1=1-tan^2(pi/8)/tan(pi/8)=2/tan(2xxpi/8)=2/tan(pi/4)=2`
25.

Let A and B be 2xx2 matrices with real entries . Let I be the 2xx2 indentity matrix. Denote by tr (A) the sum of diagonal entries of A . Statement -1 : AB -BA ne I Statement -2 : tr (A+B ) = tr (A) +tr (B) and tr (AB) =tr (BA)

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ANSWER :A
26.

No. of distinct terms in (x + y - z)^16 is

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154
126
133
153

Answer :D
27.

1+(2)/(4) + (2.5)/(4.8)+(2.5.8)/(4.8.12)+(2.5.8.11)/(4.8.12.16)+…..=

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`4^(-2//3)`
`ROOT(5)(16)`
`root(3)(4)`
`4^(2//3)`

Answer :C
28.

Rajesh agrees to play the game of tossing dice. If number 1 or 2 comes up he looses ₹ 2 and if number 3 or 4 or 5 comes up he gets ₹ 5 and he loose ₹ 10 if number 6 comes up. If random variable X denotes the amount get by Rajesh then find expectation.

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ANSWER :`(7)/(2)`
29.

Statement-1 : z_(1)^(2) + z_(2)^(2) +z_(3)^(2) +z_(4)^(2) =0 " where " z_(1) ,z_(2),z_(3) and z_(4) are the fourth roots of unity and Statement -2 :(1)^(1/4) = (cos0^(@) +isin0^(@))^(1/4)

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Statement -1 is True, Statement -2 is True, Statement -2 is a correct EXPLANATION for statement -4
Statement -1 is True, Statement -2 is True , Statement -2 is NOT a correct explanation for Statement -4
Statement -1 is True, Statement -2 isFalse
Statement -1 is FLASE, Statement -2 is True

Answer :A
30.

If the system of linear equations x+2ky+3z=0 3x+2ky-2z=0 2x+4y -3z=0has a non -zero solution (x,y,z) then |(yz)/(2x^(2))|=____

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ANSWER :`0.04`
31.

Number of integral values of 'x' satisfying |x+4|+|x-4|=8 is :-

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8
6
9
7

32.

Area of the triangle formed by the lines through point (6, 0) and at a perpendicular distance of 5 from point (1, 3) and liney = 16in square units is :

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160
200
240
130

Answer :C
33.

In a certain college , 40% of the men and 10% of the women are taller than 2 meters. Further more in the college 60% of the students are women. If a student selected at random is found to be taller than 2 meters,the probability that the selected student is awoman is

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`(3)/(11)`
`(8)/(11)`
`(5)/(11)`
`(6)/(11)`

ANSWER :A
34.

lim_(ntooo)1/n{sin^(5)(pi/(6n))+sin^(5)((2pi)/(6n))+sin^(5)((3pi)/(6n))+...+sin^(5)(pi/2)}=

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`8/(15pi)`
`8/(5PI)`
`32/(5pi)`
`16/(5pi)`

ANSWER :D
35.

3^(2(n-1)) + 7 is divisible by 8 for every natural n ge 2.

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SOLUTION :Let `P_n = 3^(2(n-1)) + 7`
When `n =2. 3^2 + 7 = 16` is divisible by 8.
`THEREFORE P_2` is true.
`P_k` be true. i.e, `3^(2(k-1)) + 7` is divisible y 8. Let `3^(2k-2) + 7` = 8m. M in Z . Now `3^(2(k+1-1) +7 = 3^2k + 7`
`3^(2k-2).3^2 + 63-56`
= `9(3(2k-2) + 7)-56`
= `9 xx 8m - 56` = 8(9m-7) Which is divisible by 8.
`therefore P_(k+1)` is true.
`therefore P_n` is true for all values on `n le 2`
36.

Rajat observes that the angle of elevation of the first floor of a building at a point A on the ground is 30^(@). He moves sqrt(3) units towards the building to the point B and finds that the angle of elevation of the second floor of the building is 60^(@). If each floor has the same height, height of the 7th floor from the ground in units is

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5
7
21
35

Answer :C
37.

lim_(x rarr 0) ((tan x - x)/(x)) sin ((1)/(x)) is :

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a real number other than 0 and 1
0
1
None of these

Answer :C
38.

Find the number of positive integers n such that 105 is a divisor of n^(2)+n+1

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SOLUTION :The digit in the unit place of `n(n+1)+1` is 1,3, or 7
`IMPLIES` 5 does not divides `n^(2)+n+1`
`implies` 105 is not a divisor of `n(n+1)+1`,
39.

Let S_(2) = 0 is the mirror image of S_(1) : x_(2) + y_(2) – 4x – 6y + 12 = 0 w.r.t the line L_(1) : 10^(4)x + (10^(4) + 10)y + (10^(4) + 20) = 0. Let L_(2) : 2^(11) x + (2^(11) + 2^(12))y + (2^(11) + 2^(13)) = 0 be a line then the equations of line passing through the point of intersection of the line L^(2) = 0 with radical axes of S_(1) = 0, S_(2) = 0 and making equal intercepts in magnitude with the coordinate axes is/are

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) x – y – 3 = 0
x + y + 1 = 0
2x – 2Y + 1 = 0
2x + 2y + 3 = 0

Answer :A::B
40.

The plane passes through the point (1,-1,-1) and its normal is perpendicular to both the lines (x-1)/(1) = (y+2)/(-2) = (z-4)/(3) and (x-2)/(2) + (y+1)/(-1) = (z+7)/(-1). The distance of the point (1,3,-7) from thise plane is ..........

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`(10)/(SQRT(74))`
`(20)/(sqrt(74))`
`(10)/(sqrt(83))`
`(5)/(sqrt(83))`

ANSWER :C
41.

Integrate the following functions (1+logx)^2/x

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SOLUTION :Let t = 1+logx. Then DT = 1/x dx.
` THEREFORE INT (1+logx)^2/x dx = int t^2dt`
= `t^3/3 +c = (1+logx)^3/3 +c`
42.

Differentiate the following w.r.t. x : cot(logx+e^(sqrtx))

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ANSWER :`-(1/x+(E^(SQRTX))/(2sqrtx))COSEC^(2)(logx+e^(sqrtx))`
43.

Two numbers x and y are selected at random from the set {1, 2, 3,… 3n}. Find the probability that x^(2) - y^(2) is divisible by 3.

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ANSWER :`(5)/(9)`
44.

Evaluate int(x^(2)e^(x))/((x+7)^(2))dx

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ANSWER :`(X-2)/(x+2)E^(x)+C`
45.

Given the following table Computeri) E(4X+5) ii) E(X^(2)) iii) V(X)iv) V(2X+-3)

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ANSWER :i) 6II) 2.95iii) 1.8875iv) 7.55
46.

If centre (1, 2), axes are parallel to co-ordinate axes, distance between the foci 8, e = (1)/sqrt(2)then equation of the ellipse is

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`(x-1)^(2)/(32)+(y-2)^(2)/(16)=1`
`(x-1)^(2)/(16)+(y-2)^(2)/(8)=1`
`(x-1)^(2)/(64)+(y-2)^(2)/(8)=1`
`(x-1)^(2)/(24)+(y-2)^(2)/(12)=1`

Answer :A
47.

The position vector of the point which divides the join of points 2bar(a)-3bar(b) and bar(a)+bar(b) in the ratio 3 : 1, is ………….

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`(3BAR(a)-2BAR(b))/(4)`
`(7bar(a)-8BAR(b))/(4)`
`(3bar(a))/(4)`
`(5bar(a))/(4)`

ANSWER :D
48.

Which of the following is equivalent to (x ^(2) + 3x + 7)/(x +4 ) ?

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`(3+7)/(4 )`
`X + 3/4`
`3 + (7)/(x +4)`
`x -1 + (11)/(x +4)`

ANSWER :D
49.

If f(x)={{:(cos^(-1) (cotx),","x lt pi/2),(a(x[x]-1),"," x ge pi/2):} The value of a for f to be continuous at x=pi/2 is

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`PI/(2(pi-1))`
`pi-1`
`pi/(pi+1)`
`pi/(pi-1)`

ANSWER :A
50.

If (tan 3A)/(tan A) =a then (sin 3A)/(sin A) is equal to

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`(2A)/(a +1)`
`(2a)/(a -1)`
`(a )/( a +1)`
`(a )/(a-1)`

ANSWER :B