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.

Statement I : Thecommon regiondetermined by all the constraints of a LPP is called the feasible region Statement II : A solutionthat also satisfies the non negativtiy restrications of a LPP is called the feasible soltion

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Statement I is TRUE Statement II is true , Statement II is a CORRECT explanatio for Statement I
Statement I is true Statement II is true ,Statement II is not a correct EXPALNATION forStatement I
Statement I is true Statement II is false
Statement I is false StatementII is true

ANSWER :A
2.

Answer the folliwng as true of false. (i) vec(a) and vec(a) and collinear. (ii) Zero vector is unique. (iii) Two collinear vectors with equal magnitude are not equal.

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ANSWER :(i) TRUE (II) FALSE (ii) True
3.

p-=q(mod m) if and only if

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<P>`(p-Q)/(m)`
`(m)/(p-q)`
`(m)/(p)`
`(m)/(q)`

ANSWER :B
4.

If alpha, beta, gammabe any three arbitrary angles then cos alpha, cos beta, cos gammacan always be considered as the direction cosines of a line.

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ANSWER :F
5.

Minimum length of a normal chord to the hyperbola xy = c^(2) lying between different branches is

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`sqrt2c`
`2 C`
`2 SQRT 2 c `
NONE of these

SOLUTION :N/A
6.

Some standard forms of integration : intsqrt(x^(2)-4x+2)dx=..........+c

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`(X-2)/(2)sqrt(x^(2)-4x+2)+log|x-2+sqrt(x^(2)-4x+2)|`
`(x-2)/(2)sqrt(x^(2)-4x+2)-log|x-2+sqrt(x^(2)-4x+2)|`
`(x-2)/(2)sqrt(x^(2)-4x+2)+sin^(-1)((x-2)/(2))`
`(x-2)/(2)sqrt(x^(2)-4x+2)+(1)/(2)sin^(-1)((x-2)/(2))`

Answer :B
7.

Let bara, barb and barc be mutually orthogonal vectors of equal magnitudes. Prove that the vector bara+barb+barc is equally inclined to each of bara, barb and barc, the angle of inclination beingcos^(-1)" 1/sqrt3

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ANSWER :`Cos^(-1)(1)/(SQRT(3))` with `barb" and "barc`.
8.

If a,b,c and d are the roots of the equation x^(4)+2x^(3)+4x^(2)+8x+16=0 the value of the determinant |{:(1+a,1,1,1),(1,1+b,1,1),(1,1,1+c,1),(1,1,1,1+d):}| is

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ANSWER :8
9.

Compute the area of the surface formed by revolving about the straight line x+ y=a the quarter of the circle x^(2) + y^(2)=a^(2) between A(a, 0) and B(0, a).

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ANSWER :`=(PI a^(2))/(SQRT2) (4- pi)`
10.

Prove that the distance between the circumcenter and the orthocenter of triangle ABC is R sqrt(1 -8 cos A cos B cos C)

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Solution :Let O and H be the circumcenter and the orthocenter, respectively.
If OF is the PERPENDICULAR to AB, we have
`angleOAF = 90^(@) - angle AOF = 90^(@) -C`

Also, `angleHAL = 90^(@) -C`
Hence, `angle OAH = A - angle OAF - angle HAL`
`= A -2 (90^(@) -C)`
`= A + 2C -180^(@)`
`= A + 2C -(A + B +C) = C -B`
Also, `OA = R and HA = 2R cos A`
Now in `Delta AOH`
`OH^(2) = OA^(2) + HA^(2) - 2OA HA cos (angle OAH)`
`=R^(2) + 4R^(2) cos^(2) A - 4R^(2) cos A cos (C -B)`
`= R^(2) + 4R^(2) cos A [cos A - cos (C -B)]`
`=R^(2) -4R^(2) cos A [cos (B + C) + cos (C - B)]`
`= R^(2) -8R^(2) cos A cos B cos C`
Hence, `OH = R sqrt(1-8 cos A cos B cos C)`
11.

If z + (1)/(z) = -1then z^(5) + (1)/(z^(5)) =

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1
`-1`
`OMEGA`
`omega^(2)`

ANSWER :B
12.

If the line ax + y = c, touchs both the curves x^(2) + y^(2) = 1 and y^(2) = 4 sqrt(2)x, then |c| is equal to

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`(1)/(SQRT(2))`
2
`sqrt(2)`
`(1)/(2)`

Solution :Use the equation of tangent of slope 'm' to the parabola `y^(2) = 4 ax` is `y = mx + (a)/(m)` and a line ax + by + c = 0 touch the circle
`x^(2) + y^(2) = R^(2)`, if `(|c|)/(sqrt(a^(2) + b^(2)) = r`
Since equation of given parabola is `y^(2) = 4 sqrt(2x)` and equation of tangent line is ax + y = c ory = - ax + c
then `c = (sqrt(2))/(m) = (sqrt(2))/(-a)`[`:.` m = slope of line = - a]
[`:'` line y = mx + c touches the parabola
`y^(2) = 4ax` if c = a/m]
Then, equation of tangent line BECOMES
`y = - ax - (sqrt(2))/(a)` ......(i)
`:.` Line (i) is also tangent to the circle `x^(2) + y^(2) = 1`
`:.` Radius = 1 = `(|-(sqrt(2))/(a)|)/(sqrt(1 + a^(2)) implies sqrt(1 + a^(2)) = | - (sqrt(2))/(a)|)`
`implies 1 + a^(2) = (2)/(a^(2))` [squaring both side]
`implies a^(4) + a^(2) - 2 = 0 implies (a^(2) + 2) (a^(2) - 1) = 0`
`implies a^(2) = 1``[:. a^(2) gt 0, AA a in R]`
`:. |c| = (sqrt(2))/(|a|) = sqrt(2)`
13.

1.""^20C_1 - 2.""^20C_2 + 3.""^20C_3 - …..-20.""^20C_20 =

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1
2
`-1`
0

Answer :D
14.

Let f: (1 to infty) to (1, infty) be defined by f(x) =(x+2)/(x-1). Then

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F is 1 - 1 and ONTO
f is 1 - 1 but not onto
f is not 1 - 1 but onto
f is NEITHER 1 - 1 nor onto

Answer :A
15.

int (2x^2-1+x^2 sqrt(x^2+4))/(x^2(x^2+4))dx

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`9/8tan^(-1) x/2+1/(4x)+cos h^(-1)x/2+C`
`9/8 "tan"^(-1)x/2+1/(4x)+"SIN" h^(-1)x/2+c`
`9/16"log"|(x+2)/(x-2)|+1/(4x)+"log|(x+sqrt(x^2+4))/(2)|+C`
`(-9)/(16)log|(2-x)/(2+x)|+1/(4x)+"cos"h^(-1)x/2+C`

Answer :B
16.

Find the sum of the infinite series (3)/(4)+(3.5)/(4.8)+(3.5.7)/(4.8.12)+….

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SOLUTION :N/A
17.

Let A=[(2, -1, 1),(-2, 3, -1),(-4, 4, -x)] be a matrix. If A^(2)=A, then the value of x is equal to

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ANSWER :2
18.

If z = x +iy and P represents z in the Argand plane and mod (2z-3) = 4 , then the locus of P is

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`(2 x- 3)^(2) - 4y^(2) = 16`
`(2X +3)^(2) + 4y^(2) = 12`
`(2x - 3)^(2) + 4y^(2) = 16`
`(2x + 3)^(2) - 4y^(2) = 12`

Answer :C
19.

State whether the following statements are true or false. Justify If ** is a commutative binary operation on N, then a**(b**c)=(c**b)**a

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SOLUTION :`a**(b**C)=a**(c**b)=(c**b)**a,`
for all `a,b,c in N`
`THEREFORE ` The given STATEMENT is TRUE
20.

Find the points of maximaminima of f(x) =x^(3) -12 x. Alsodraw the graph of this functions.

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Solution :`F(x) =x^(3) -12x`
`f'(x) =3(x^(2)-4) =3(x-2) (x+2)`
`RARR""x= +- 2`

fortracingthe graphlet usfindmaximum and minimum VALUES of (x) .
21.

If f(t)=int_(-t)^(t)(e^(-|x|))/(2)dx" then "lim_(ttooo)f(t)=

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1
`1//2`
0
-1

Answer :A
22.

If A_l=(x-a_i)/(|x-a_i|)30, i=1,2,..., n and if a_1 lt a_2 lt a_3lt ..... lta_n. Then, lim_(xtoa_m) (A_1A_2.....A_n), 1 le mle n

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is EQUAL OT `(-1)^m`
is equal to `(-1)^m+1`
is equal to `(-1)^m-1`
does not EXIST.

ANSWER :D
23.

If the remainders respectively when f(z) = z^(3)+z^(2)+2z+1 is divided with z-i and z+i and 1+3i and 1+i then find the remainder when f(z) is divided with z^(2)+1 ?

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ANSWER :`z+1+2i`
24.

Find the number of ways of arranging 'r' things in a line using the given 'n' different things in which atleast one thing is repeated.

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ANSWER :`n^r-""^nP_r`
25.

Prove that : If the coefficientsof (2r+4)^("th") and (r-2)^("nd") terms in the expansion of (1+x)^(18) are equal, find r.

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SOLUTION :N/A
26.

Which of the following is logically equivalent to ~(~q rarr p) ?

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<P>`Q ^^ p`
`q ^^ ~p`
`~q ^^ p`
`~q ^^ ~p`

ANSWER :A
27.

If log(x^(2)y^(3))=a and log(x)./(y)=b find log x and logy in terms of a and b

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ANSWER :A::B::C::D
28.

If m is the A.M. of two distinct real number l and n (l, n gt 1) and G_(1), G_(2) and G_(3) are three geometrc means between l and n then G_(1)^(4)+2G_(2)^(4)+G_(3)^(4) equals.

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`4 L^(2) m n `
`4 l m^(2) n`
`4 l MN^(2)`
`4l^(2) m^(2) n^(2)`

Answer :B
29.

In a bolt factory three machines A, B and C manufactures bolts 25%, 35% and 40% respectively. From this production 5%, 4% and 2% bolts are defective from machines respectively. A bolt is drawn at random from the product what is the probability of the event that the selected bolt is defective ?

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ANSWER :0.41
30.

If A+B is a non -singular matrix then A-B -A(A+B)^(-1)A+B(A+B)^(-1) Bequals

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O
I
A
B

Answer :A
31.

intdx/(e^x-1)

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SOLUTION :`I=intdx/(e^x-1)`
=`inte^-x/(1-e^-x)DX`
LET `1-e^-x=t`
`e^-xdx=dt`
`THEREFORE I=intdt/t`
=`Inabst+C`
=`Inabs(1-e^-x)+c`
=`Inabs((e^x-1)/e^x)+c`
32.

If (6,8),(k,2)are inverse points w.r.t the circle x^(2)+y^(2)=25 then 2k=

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1
3
5
7

Answer :B
33.

Evaluate the following intergrals : intsqrt(4-3x-3x^(2))dx

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ANSWER :`=SQRT(3)[(2x+1)/(4)sqrt((4)/(3)-x-x^(2))+(19)/(24)sin^(-1){(sqrt(3)(2x+1))/(sqrt(19))}]+c`.
34.

int("log"x)^(3) x^(5)dx=

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`x^(8)[((logx)^(3))/(12)-(1)/(2)(logx)^(2)+(1)/(6)logx-(1)/(36)]+c`
`x^(6)[((logx)^(3))/(6)-(1)/(18)(logx)^(2)+(logx)/(12)-(1)/(36)]+c`
`x^(6)[((logx)^(3))/(6)+(1)/(12)(logx)^(2)-(logx)/(12)+(1)/(36)]+c`
`x^(6)[((logx)^(3))/(6)-((logx)^(2))/(12)+(logx)/(36)-(1)/(216)]+c`

Answer :D
35.

Using the property of determinants andd without expanding in following exercises 1 to 7 prove that |{:(1,x,x^2),(x^2,1,x),(x,x^2,1):}|=(1-x^3)^2

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ANSWER :`(1-x^3)^2`
36.

int_(pi//2)^(0)sin^(11)xdx

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SOLUTION :N//A
37.

If costheta =4/5,then find the value of cos2theta.

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38.

Using the property of determinants andd without expanding in following exercises 1 to 7 prove that |{:(1,1,1),(a,b,c),(a^3,b^3,c^3):}|=(a-b)(b-c)(c-a)(a+b+c)

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ANSWER :`(a-b)(b-c)(c-a)(a+b+c)`
39.

Using the property of determinants andd without expanding in following exercises 1 to 7 prove that |{:(1,a,a^2),(1,b,b^2),(1,c,c^2):}|=(a-b)(b-c)(c-a)

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ANSWER :`(a-b)(b-c)(c-a)`
40.

Expand the binomial ((x^(2))/(3) + (3)/(x))^(5)

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Answer :`(x^(10))/(243) + (5)/(27) x^(7) + (10)/(3) x^(4) + 30X + (135)/(x^(2)) + (243)/(x^(5))`
41.

If 4.05^(p) = 5.25^(q) , what is the value of (p)/(q) ?

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<P>`-0.11`
`0.11`
1.19
`1.30`

Solution :Take `LOG _(4.05)` of both SIDES of the equation , getting p = `log _(4.05) 5.25^(Q)` , or `p = q log _(4.05) 5.25` . Dividing both sides by q and changing to base 10 yields `(p)/(q) = (log 5.25)/(log 4.05) ~~ 1.19`
42.

Two circles with radii r_1 and r_2, r_1 gt r_2 ge 2,touch other externally. If 'alpha' be the angle between direct common tangents ,then

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` alpha = SIN ^(-1)((r_1 +r_2)/( r_1-r_2)) `
` alpha = 2 sin ^(-1)((r_1-r_2)/( r_1+r_2))`
` alpha =sin ^(-1)((r_1-r_2)/( r_1+r_2)) `
`alpha =sin ^(-1) ((r_1)/(r_1))`

ANSWER :B
43.

Evaluate int secx ( sec x + tan x ) dx

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ANSWER :`INT ( sec^(2) x + sec x tan x ) DX = tan x + sec x + C`
44.

int_(-pi)^(pi) x^(3) Cos x dx=

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1
0
-1
`PI`

ANSWER :B
45.

If the median of the data 6,7,x-2,18,21 written in ascending order is 16, then the variance of that data is

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`30(1)/(5)`
`31(1)/(3)`
`32(1)/(2)`
`33(1)/(3)`

ANSWER :B
46.

If cosec^(-1)(x) + sec^(-1)(sqrt(x^4 + 1)) + tan^(-1) (x^2 + 1) = pi ( x > 0) then x =

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`1`
`2`
`sqrt(2)`
`sqrt(3)`

Solution :CHECK by SUBSTITUTING the value of X.
47.

int(x-1)/((x+1)^(3))e^(x)dx=.......+c

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`(E^(X))/((x+1)^(2))`
`(-e^(x))/((x+1)^(2))`
`(e^(x))/((x+1)^(3))`
`(-e^(x))/((x+1)^(3))`

ANSWER :A
48.

The value of log_(e) (5^(13/2)) is between which of the following pairs of consecutive integers?

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0 and 1
4 and 5
5 and 6
6 and 7

Answer :D
49.

Find int (xdx)/((x-1)(x-2))

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`LOG|(x-1)^2/(x-2)|+C`
`log|(x-2)^2/(x-1)|+c`
`log|((x-1)/(x-2))^2|+c`
`log|(x-1)(x-2)|+c`

ANSWER :B
50.

Draw the graph of y=|||x|-2|-3| by transforming the graph of y=|x|

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SOLUTION :