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 mean deviation of the number 1, 1+d, 1+2d,….,1+100 d from their means is 255, then the d is equal to

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`20.0`
10.1
20.2
`10.0`

ANSWER :B
2.

Find the slope of the normal to the curve x=1 -a sin theta , y = b cos^(2) thetaat theta= (pi)/(2) .

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ANSWER :`(-a)/(2B)`
3.

Function 'f:RrarrR,f(x)=3x-5' is :

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ONE to one
ONTO only
one-one and onto
none of these

Answer :C
4.

Evaluate the following lim_(xto2) (x^2 +3x -9)/(x+1)

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SOLUTION :`lim_(xto2) (x^2 +3X -9)/(x+1)`
`=(2^2+3cdot2-9)/(2+1)=1/3`
5.

Find (dy)/(dx) in the following: y= sec^(-1) ((x^(2) + 1)/(x^(2)-1))

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ANSWER :`(-2)/(1+x^(2))`
6.

Consider the relation 4l^(2)-5m^(2)+6l+1=0 , where l,m in R Tangents PA and PB are drawn to the above fixed circle from the points P on the line x+y-1=0 . Then the chord of contact AP passes through the fixed point.

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`(1//2,-5//2)`
`(1/3,4//3)`
`(-1//2,3//2)`
none of these

Solution :Let the equation of the circle be
`X^(2)+y^(2)+2gx+2fy+c=0`(1)
The line `lx +my+1=0` will touch circle (1) if the length of perpendicular from the center `( -g, -f)` of the circle on the line is equal to its radius, i.e.,
`(|-g l =mf +1|)/(sqrt(l^(2)+m^(2)))=sqrt(g^(2)+f^(2)-c)`
`(gl+mf-1)^(2)= (l^(2)+m^(2))(g^(2)+f^(2)-c)`
or `(c-f^(2))l^(2)+(c-g^(2))m^(2)-2gl-2fm+2fglm+1=0`(2)
But the given condition is
`4l^(2)-5m^(2)+6l+1=0`(3)
Comparing (ii) and (iii), we GET
`c-f^(2)=4,c-g^(2)= -5, -2g = 6, -2f =0, 2gf=0`
Solving, we get
`f=0, g= -3, c=4`
Substituting these values in (1) , the equation of the circle is `x^(2)+y^(2)-6x+4=0`. Any point on the ling `x+y-1=0` is `(t, 1-t) , t in R`. The chord of contact w.r.t. this point of circle is `TX +y(1-t) -3(t+x) +4 =0` or `t ( x-y-3) + (-3x+y+4)=0`, which is concurrent at the point of intersection of the lines `x-y-3=0` and `-3x+y+4=0` for all values of t. Hence, the lines are concurrent at `(1//2, -5//2)`. Also point (2,-3) lies outside the circle from which TWO tangents can be drawn.
7.

Consider the planes p_1: 2x+y+z+4=0, p_2: y-z+4=0 and p_3: 3x+2y+z+8=0 Let L_1, L_2, L_3 be the lines of intersection of the planes p_2 and p_3, p_3 and p_1, p_1 and p_2 respectively. Then.

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at LEAST two of the line `L_1, L_2 and L_3` are non parallel.
at least two of the LINES `L_1, L_2 and L_3` are parallel
the three PLANES INTERSECT in the line.
the three planes form a triangular prism.

Answer :(B, c)
8.

If forafunctionf :R to Rf (x +y ) =F(x )+ f(y)for allx andy thenf(0)is

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t
0
anyrealnumber
`-1`

ANSWER :B
9.

Find the coefficient of x^(-6)" in "(3x-(4)/(x))^(10)

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ANSWER :`405 XX 4^8`
10.

Consider three sets A = {1, 2, 3}, B = {3, 4, 5, 6}, C = {6, 7, 8, 9}. R_(1) is defined from A to B such that R_(1) = {(x, y) : 4x lt y, x in A, y in B}. Similarly R_(2) is defined from B to C such that R_(2) = {(x, y) : 2x le y, x in B and y in C} then R_(1)oR_(2)^(-1) is

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{(3, 1)}
{(1, 1)}
{(1, 3)}
`PHI`

ANSWER :D
11.

The slope of a curve at any point on it is the reciprocal of twice of ordinate at that point. If the curve passes through (4,3) then the equation is

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`y^(2) = x+4`
`y^(2) = x+7`
`y^(2) = x+5`
`y^(2) = x+9`

ANSWER :D
12.

The normal to x^(2)=4y passing through (1, 2) has equation ……….

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`x+y=3`
`x-y=3`
`x+y=1`
`x-y=1`

ANSWER :A
13.

If f: R to R" is definedby f(x)"=[x-3]+[x-4]"for "x in R"then " underset(x to 3-)"Lt"f(x)=

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`-2`
`-1`
0
1

Answer :C
14.

Let Q be a point on the circle B : x ^(2) + y ^(2)=a ^(2) and p(h,k) be a fixed point. If the locus of the point which divides the join of P and Q in the ratio p:q is a circle C, then the centre of C is

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<P>`((p+q)/(P), (p+q)/(q))`
`((HP + kq)/(p), (hp + kq)/(q))`
`((HQ)/(p +q), (kq)/(p +q))`
`((hq)/(p+q), (kq)/(p +q))`

ANSWER :D
15.

Prove that : log_ea-log_eb=2[(a-b)/(a+b)+1/3((a-b)/(a+b))^3+1/5((a-b)/(a+b))^5+...],a > b

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7

Solution :LET`(a-b)/(a+b)=a` in the R.H.S.`thereforeR.H.S.=2[x+x^2/3+x^5/5+...]=log((1+x)/(1-x))=log(1+(1-b)/(a+b)/1-(a-b)/(a+b))=log((2A)/(AB))=loga-logb=L.H.S`
16.

The value of lim_(ntooo){(sqrt(3)+1)^(2n)} is……..(where {.} denotes fractional part of x).

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ANSWER :1
17.

The number of ways in which 7 pencils, 6 books and 5 pens be disposed off is

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336
334
335
210

Answer :C
18.

Evaluate : (i) Find the value a such int_(0)^(a)(1)/(e^(x)+4e^(x)+5)dx = ln 3sqrt(2). (ii) Find the value of int_(0)^((pi//2)^(1//2))x^(5).sinx^(3)dx

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SOLUTION :N//A
19.

Prove that the portion of the tangent intercepted between the point of contact and the directrix of the parabola y^(2) =4ax subtends a right angle at its focus.

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ANSWER :`PQ` subtends a right angle at the FOCUS of the PARABOLA.
20.

Let A = {1,2,3},B = {4,5,6,7} and let f={(1,4),(2,5),(3,6)} be a function from A to B. Show that f is one - one.

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SOLUTION :N/A
21.

The time T of oscillation of a simple pendulum of length L is governed by T=2pisqrt(L/g), where g is a constant. The percentage by which the length be changed in order to correct an error of loss equal to 2 minutes of time per day is

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`-5/18`
`-2/9`
`1/6`
`1/9`

ANSWER :A
22.

For the process : H_(2)O (l, 1 atm, 373 K) rArr H_(2)O(g, 1 atm, 373 K) [Given normal boiling point of water = 373 K at 1 atm pressure.] The correct set of thermodynamic parameter is :

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`DeltaG = 0, Delta U lt 0, Delta H lt 0`
`DeltaS_("totale")= 0, q GT 0, DeltaS_(surr) lt 0`
`DeltaG lt 0, DELTAU gt 0, Delta H = 0`
NONE of these

Answer :B
23.

Solve the following systems of linear inequalities graphically : x - 2y + 2 lt 0 , x gt 0

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SOLUTION :
24.

The value ofhati.(hatjxxhatk)+(hatixxhatk).hatj…….

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1
` -1 `
0
` HATJ `

ANSWER :C
25.

Show that the lines joining the origin with the points of intersection of the curve 7x^2-4xy+8y^2+2x-4y-8=0 with the line 3x-y=2 are mutually perpendicular.

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ANSWER :The PAIR of LINES are MUTUALLY PERPENDICULAR.
26.

Mother,Father and Son line up at random for a family picture.E : son on one end, F:Father in middle. Find P(E/F).

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Solution :SUPPOSE A,B,C denote the mother, the father and the son respectively.
Then S ={ABC,ACB,BAC,BCA,CAB,CBA} `rArr` n(S) = 6
E = {CAB,CBA,ABC,BAC}, F={ABC,CAB} `rArr` n(F)=2
Also,`EnnF`={ABC,CAB}`rArr` n`(EnnF)` = 2
therefore`P(EnnF)`=2/6 and P(F) =2/6 `rArr` P(E/F) = `(P(EnnF))/P(F))`=1
27.

If f(a)=2, f'(a)=1, g(a)=3, g'(a)=-1, then underset(x to a)lim (f(a)g(x)-f(x)g(a))/(x-a) is equal to

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6
1
`-1`
`-5`

ANSWER :D
28.

If p + q = 12 and pq = 35, then 1/p + 1/q =

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`1//5`
`1//7`
`1//35`
`12//35`

ANSWER :D
29.

Extend the function f(x)=x^2 + x defined on the interval (0,3) onto the interval(-3, 3) in an even and an odd way.

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Answer :An EVEN extension defines the FUNCTION `phi(x)={{:(,f(x)=x^(2)+x" for "0 le x le 3),(,f(-x)=x^(2)-2" for "-3 le x LT0):}`
An odd EXTENSIONS defines the function
`PSI(x) ={{:(,f(x)=x^(2)+x" for "0 le x le 3),(,-f(x)=-x^(2)+x" for "-3 le x lt 0):}`
30.

The probability for a randomly chosen month to have its 10^(th) day as Sunday is

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`(1)/(7)`
`(5)/(6)`
`(5)/(42)`
`(1)/(12)`

Answer :A
31.

If Delta ne 0 then the system is ............... .

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CONSISTENT and has UNIQUE solution
Consistent and has INFINITELY MANY solutions
Inconsistent
Either consistent or inconsistent

Answer :A
32.

Differentiate w.r.t.x the function in Exercises 1 to 11. (sin x- cos x)^( sin x - cos x), (pi)/(4) ltx lt (3pi)/(4).

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Answer :`(SIN x- COS x)^(sin x-cos x)(cos x+ sin x)(1+ log(sin x-cos x)); sinx gt cos x`
33.

Differentiate the functions given in Exercises 1 to 11 w.r.t. x. (logx)^(x)+ x^(log x).

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ANSWER :`(LOGX^(X-1) [1+LOG x. log(logx)]+2X^(log x-1).logx`.
34.

A ball is thrown upward with such a velocity v that it returns to the thrower after 3 s. Take g = 10 ms^(-2). Find the value of v :-

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15 m/s
20 m/s
10 m/s
5 m/s

Answer :A
35.

If A and B are two independent events, then the probability of occurrence of atleast one of A and B is given by

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<P>`1-P(A).P(B)`
`1-P(A).P(B`)`
`1-P(A`).P(B)`
`1-P(A`).P(B')`

ANSWER :D
36.

If is the sum of the n^(th)powers , p is the sumof the products of m together of the n quantities a_(1),a_(2),……a_(n) eachof whichis greater than1 , show that (n-1) !s gt (n-m) ! …m! p

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<P>

ANSWER :`RARR .^(n)C_(m)s/n GT p rArr (n-1)S gt (n-m)!m ! p `
37.

The volume of a cube is increasing at the rate of increasing at the instant when the length of an edge of the cube is 24 cm?

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ANSWER :`(7)/(6)CM^(2)//s.`
38.

intsinx.log (sinx) dx. =

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`-`COSX.LOG (sinx) + log `|tan""(x)/(2)|` + cos x + C
`-`cosx.log (sinx) + cosx + c
`-`cosx.log (sinx) - log `|tan""(x)/(2)|` + c
`-`cosx.log (sinx) + log `|COT""(x)/(2)|` + cos x + c

ANSWER :A
39.

One limiting point of the coaxal system of circles containingx^(2) + y^(2) - -6x - 6y + 4 = 0 " and " x^(2) + y^(2) - 2x - 4y + 3 = 0is

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(-1,1)
(-1,2)
(-2,1)
(-2,2)

ANSWER :A
40.

Using differentials, find the approximate value of(25)^(1/3).

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ANSWER :`=2.926`
41.

The shortest distance the lines (x-3)/(3) = (y-8)/(-1) = (z-3)/(1) and (x+3)/(-3) = (y + 7)/(2) = (z-6)/(4) is..........

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`SQRT(30)`
`2 sqrt(30)`
`5sqrt(30)`
`3sqrt(30)`

ANSWER :D
42.

A fair coin is tossed n times. Let x be random variable denoting the number of heads tossed. If P(x=4), P(x=5),P(x=6) are in A.P. then n =

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7
10
14
7 or 14

ANSWER :D
43.

Aline in 3 dimensional space makes an angletheta (0 lt theta le pi//2)with both the x and y axex . Then the set of all values ofthetais the interval

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`(0, (PI)/(4))`
`[(pi)/(6),( pi)/(3)]`
` [(pi)/(4),(pi )/(2) ]`
` [(pi )/(3),( pi )/(2) ]`

Answer :C
44.

Prove the following : cot22(1/2)^@=sqrt2+1

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SOLUTION :`COT(45^@/2)=(1+cos45^@)/(SIN45^@)=(1+1/sqrt2)/(1/sqrt2)`
`sqrt2+1`
45.

A tower of height b subtends an angle alpha at a point on the same level as the food of the tower .At a second point , b meters above the first , the angle of depression of the foot pole and the finds that the elevation is now 2 theta.The value of cot thetais

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B COT `alpha "TAN " beta `
`b tan alpha tanbeta `
`b tan alpha cot beta`
`b cot alpha cot beta`

Solution :Let AB be the tower of height h, D be the point x away fron B and C be another point b m above D

In triangle ABD.
`h=x tan alpha`
In triangle BCE. `X= b cot beta`
from (1) and (2) we get
`thereforeh=b tan alpha cot beta`
46.

Evaluate{:|( x,y , x+y),( y,x+y,x),( x+y,x,y)|:}

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ANSWER :`-2(X^(3) +y^(3)) `
47.

integrate the following inte^(2x+7)dx

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Solution :`inte^(2x+7)DX`
[put 2x+7=t
2dx=dt or dx=(1/2)dt]
`inte^tcdot (1/2)dt =(1/2)e^t+C =(1/2)e^(2x+7)+C`
48.

Find the area bounded by the parabola y=x^(2),the x -axis and the lines x=-1, x=2 .

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ANSWER :3
49.

Consider the binary operation ** on the set A= {1,2,3,4,5} given by the following multiplication table Compute (2**3)**4 and 2**(3**4)

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SOLUTION :`(2**3)**4=1**4=1`
`2**(3**4)=2**1-1`
50.

Consider the binary operation ** on the set A= {1,2,3,4,5} given by the following multiplication table Compute (2*3)*(4*5)

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Solution :`(2**3)**(4**5)=1**1=1`