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.
| 2. |
For the binomial distribution (a + p)^(n) = ((1)/(2) + (1)/(2))^(10) if A = P (x = 3 ) , B = P (x = 6) , C = P (x = 9) then the ascending order of A , B , C is |
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Answer» C , A , B |
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| 3. |
Find the direction cosines of the unit vector perpendicular to the plane vecr.(6hati-3hatj-2hatk)+1=0 passing through the origin. |
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| 4. |
Evaluate: int _( 0 ) ^(pi) e ^(|cos x|)( 2 sin ((1)/(2)cos x )_+ 3 cos ((1)/(2)cos x ))sin x dx |
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| 5. |
If 15 boys of different ages are distributed into 3 groups of 4,5, and 6 boys randomly then the probability that three youngest boys are in different groups is |
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Answer» `24/91` |
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| 6. |
If n is an integer then show that (1 + cos theta +i sin theta)^(n) + (1 + cos theta - i sin theta )^(n)= 2^(n+1) cos ^(n) ( theta//2) cos ((n theta)/2). |
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| 7. |
Leta = hati+ hatj+ hatkand letr beavariablevectorsuchthatr . "" hati, r."" hatj , r .""Kare positiveintegersifr.ale12thenthe numberof valuesofr is |
| Answer» Answer :B | |
| 8. |
If f (x) =|sin x-|cos x ||, then f '((7pi)/(6))= |
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Answer» `(sqrt3+1)/(2)` |
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| 9. |
Solve the differential equation : (dy)/(dx) =1 + x^(2)+y^(2)+x^(2)y^(2) . |
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| 10. |
Prove that :int_(0)^(1) (log x)/(sqrt(1-x^(2)))dx=-(pi)/(2)log 2 |
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| 11. |
Evaluate the following determinants. [[1,2,3],[1,2,3],[3,4,5]] |
| Answer» SOLUTION :`[[1,2,3],[1,2,3],[3,4,5]]=0 (becauseR_1=R_2)` | |
| 12. |
(i) ifA=[{:(1,-4),(3,1):}]and b=[{:(1,0,5),(-2,4,3):}],then show that : (AB)'=B'A' implies(1)/(2)(A-A')=[{:(0,3//2,-4),(-3//2,0,7//2),(4,-7//2,0):}] Now A=(1)/(2)(A+A')+(1)/(2)(A-A') implies[{:(2,0,-4),(-3,1,5),(4,-2,3):}]=[{:(2,-3//2,0),(-3//2,1,3//2),(0,3//2,3):}]+[{:(0,3//2,-4),(-3//2,0,7//2),(4,-7//2,0):}](ii) if A=[{:(2,3),(0,1):}]and B=[{:(3,4),(2,1):}],then prove that : (AB)'=B'A' |
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| 13. |
Show that the operation * on Z define by a* b =a+b+1 for all a,b in Z Satisfies (i) the closure property (ii) the associative law and (iii) the commutative law ltrbgt (iv) find the identity element inZ (v) what is the inverse iof an element a in Z ? |
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Answer» Solution :(i) closure porperty LET a `in` A ,b in Z then a*b=a+b+1 Nowa `in` Z , b in Z `RARR` a+b in Z `rarr` a+b +1 `in` Z `therefore` * on Z satisfies the closure propety (ii) Associative law For all a,b,c `in` Z we have (a*b)*c=(a+b+1)*c =(a+b+1)+c+1 =a+b+c+2 a*(b*c)=a*(b+c+1) =a+(b+c+1)+1 =a+b+c+2 `therefore` (a*b)*c=a*(b*c) (iii) commutative law For all a,b `in` Z we have a*b=a+b+1 ltbrgeb+a+1 [`therefore` a+b+=b+1] =b*a (iv) Existence of identity element Let e be the identity element in Z Then a * e =a `rarr` a+e+1=a `rarr` =-1 Thus -1 in Z is the identity element for * (V) Existence of inverser Let a in Z and let ISTS iverse e be b then a*b=-1 `rarr` a+b+1=-1 `rarr` b =-(2+a) clearly 2`in` Z a in Z `rarr` -(2+a) `in` Z Thus each a in Z has -(2+a)in Z as its INVERSE |
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| 14. |
Radius of the circle vec(r_(2))+vecr(2hati-2hatj-4hatk)-19=0. vecr.(hati-2hatj+2hatk)+8=0, is |
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Answer» 5 |
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| 15. |
Illustrate the use of all connectives and the modified 'not' in five separate examples of propositions |
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Answer» Solution :Conjunction :HARI and Madhu are two friends. Implication : If I will be the king , then I will you my queen. Double Implication . I will love you If you will love me. Negation. I don.tlike her. |
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| 16. |
A particle performing S.H.M undergoes displacement of A//2 (where A = amplitude of S.H.M.) in one second. At t = 0 be the particle was located at either position or mean position. The time period of S.H.M. can be : (consider all possible cases) |
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Answer» 12s |
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| 17. |
A survey shows that in a city that 63% of the citizens like tea where as 76% like coffee. If x% like both tea and coffee, then |
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Answer» `x=39` |
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| 18. |
If omega is an imaginary cube root of unity, then the value of (2 - omega )(2 - omega^(2) ) + 2(3 - omega )(3 - omega^(2)) + .... .... + (n - 1)(n - omega)(n -omega^(2)) is |
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Answer» `(N^(2))/4(n+1)^(2)-n` |
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| 19. |
A plane pi makes intercepts 3 and 4respectivelyon z - axisand x- axis . If pi is parallel to y - axis , then its equation is |
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Answer» `3x+4Z = 12` |
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| 20. |
Find the values of each of the following : If "tan"^(-1)(x-1)/(x-2)+"tan"^(-1)(x+1)/(x+2)=(pi)/4, then find the value of x. |
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| 21. |
When 9th termof AP is divided by its 2nd term then quotient is 5 and when 13th term is divided by 6th term then quotient is 2 and Remainder is 5 then find first term of AP. |
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Answer» so `a+8d=5(a+d)` & `a+12d=2(a+5d)+5` `impliesa=3` |
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| 22. |
Differentiate(a^x-b^x)/x |
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Answer» SOLUTION :`y=(a^X-b^x)/x` `(DY)/(DX)=(d/dx(a^x-b^x)cdotx-(a^x-b^x)cdotd/(dx)(x))/x^2` `((a^xlna-b^xlnb)x-(a^x-b^x))/x^2` |
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| 23. |
Determine the truth of falsity of the If A is a proper subset of B and B is a subset of C Then A is a proper subset of C propositions with reasons. |
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Answer» SOLUTION :If A is a proper subset of B and B is a subset of C, then A is a proper subset of C.It is TRUE, as `X in A impliesx in B (:.A sub B)`and x in `B implies x in C(:.B sub C) x in A impliesx in C MEANS A sub C`. |
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| 24. |
Differentiate 2sqrtcot(x^2) w.r.t.x |
| Answer» SOLUTION :`d/dx(2sqrtcot(x^2))=2d/dx[sqrtcot(x^2)]=2XX1/(2sqrtcot(x^2))d/dx(COT(x^2))=1/sqrtcot(x^2)xx-cosec^2(x^2)=(-2xcosec^2(x^2))/(sqrtcot(x^2)` | |
| 25. |
If theequationwhoserootsarep timestherootsofx^4 +2x^3 +46x^2 +8x+16 =0isareciprocalequationthen p= |
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Answer» 2 |
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| 26. |
Find the equation of line passing through the given points using determinants (5,-1),(5,3) |
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| 27. |
Integrate the rational functions x/((x-1)^(2)(x+2)) |
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| 28. |
Constract the composition table/multiplication table for the binary operation * defined on {0,1,2,3,4}by a**b =axxb ("mod" =5). Find the identity element if any. Also find the inverse elements of 2 and 4. |
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Answer» SOLUTION :`A ={0,1,2,3,4}` `a**b =axx b "mod" 5` ![]() As 3rd row is identical to the FIRST row we have 1 is the IDENTITY CLEARLY `2^(-1) =3 "and" 4^(-1) =4.` |
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| 29. |
Match the following {:("I.","The approximate value of"(2*001)^4,"a",0*4983),("II".,"The approximate value of"(1*0002)^(3000),b,2.02),("III.","The approximate value of"sqrt(4*08),c,1*6),("IV.","The approximate value of" 1/(3sqrt(8*08)),d,16*032):} |
| Answer» Answer :C | |
| 31. |
A person observes the top of a tower from a point A on the ground. The elevation of the tower from this point is 60^(@). He moves 60 m in the direction perpendicular to the line joining A and base of the tower. The angle of elevation of the tower from this point is 45^(@). Then, the height of the tower (in meters) is |
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Answer» `60sqrt(3/2)` |
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| 32. |
1+(1+5)/(2!) +(1+5+5^2)/(3!) + ......oo = |
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Answer» `1/4 E(e^4 +1)` |
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| 33. |
From the top of a tower 100 m heigh, the angles of depression of two objects 200 m apart on the horizontal plane and in a line passing through the foot of the tower and on the same side of the tower are 45^(@) - A and 45^(@) + A, then angle A is equal to |
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Answer» `15^(@)` |
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| 34. |
Find the derivative of the following functions 'ab initio', that is, using the definition.t(t-1) |
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Answer» Solution :LET `y=t(t-1)=t^2-t` Then `dy/dt=lim_(DELTAT TO0)([(t+deltat)^2-(t-deltat)]-[t^2-t])/(deltat)` `=lim_(deltat to0)(t^2+2tdeltat+deltat^2-t-deltat-t^2+t)/(deltat)` `=lim_(deltat to0)[(2t-1)+deltat]=2t-1` |
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| 35. |
Evaluate the integral (a)int_(-pi)^(pi) f(x) cos nx dx (b) int_(-pi)^(pi) f(x) sin nx dxf : (1) f(x) is an evenfunction ,(2) f(x) is an odd function. |
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Answer» `int_(-pi)^(pi) f(x) cos NX DX = 2 int_(0)^(pi) f(x) cos nx dx, and int_(-pi)^(pi) f(x) sin x dx = 0 ` (2)If f(x) is an odd function, then `int_(-pi)^(pi) f(x) cos nx dx = 0`, and`int_(-pi)^(pi)f(x) sin nx dx = 2 int_(0)^(pi) f(x)`sin n dx |
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| 36. |
Find the product of the perpendiculars drawn from the point (x_1,y_1) on the lines ax^2+2hxy+by^2=0 |
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| 37. |
Find dy/dx,x=a cos'theta',y=a sin theta. |
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Answer» SOLUTION :`x=a cos theta,y=a SIN theta ` Then `DX/(d theta)=-a sin theta ` `DY/(d theta)=a cos theta fracdy/d theta` `dy/dx=(dy/(d theta))/((dx)/(d theta))=(a COSTHETA)/(-a sin theta) =-cot theta` |
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| 38. |
Write the following functions in the simplest form : tan^(-1)((cos x -sin x)/(cos x + sin x)), -pi/4 lt x lt (3pi)/4 |
Answer» SOLUTION :`tan^(-1)((cos X - sin x)/(cos x + sin x)) = tan^(-1)((cos x(1-tanx))/ (cos x(1+tanx)))` `tan^(-1)((1-tanx)/(1+tanx))= tan^(-1)tan(pi/4-x) = pi/4-x` |
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| 39. |
If int_(-3)^(2) f(x)dx= 7/3 and int_(-3)^(9) f(x)dx= - 5/6 then int_(2)^(9) f(x)dx= |
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Answer» `3/2` |
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| 40. |
If Delta ABC, A' B' C' are such that B=B', A+A'=180^@, then aa'= |
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Answer» `aa'+bb'` |
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| 41. |
There are (n + 1) white and (n + 1) black balls, each set numbered 1 to n + 1. The number of ways in which the balls can be arranged in a row so that adjacent balls are of different colours, is |
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Answer» (2N + 1) |
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| 42. |
Which one of the following vectors of magnitude sqrt(51) makes equal angles with three vectors vec(a)=(hat(i)-2hat(j)+2hat(k))/(3), vec(b)=(-4hat(i)-3hat(k))/(5) and vec(c)=hat(j)? |
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Answer» `5hat(i)-hat(j)-5hat(K)` `:.sqrt(x^(2)+y^(2)+z^(2))=sqrt(51)` `rArr x^(2)+y^(2)+z^(2)=51 " " ...(i)` Let `vec(p)` makes equal angle `theta` with and `vec(a), vec(B) and vec(c)`. `:.vec(p).vec(a)=|vec(p)|.|vec(a)|cos theta` `:. cos theta = (vec(p).vec(a))/(|vec(p)||vec(a)|)` Similarly, `cos theta = (vec(p).vec(b))/(|vec(p)||vec(b)|)` and `cos theta = (vec(p).vec(c))/(|vec(p)||vec(c)|)` `:. (vec(p).vec(a))/(|vec(p)||vec(a)|)=(vec(p).vec(b))/(|vec(p)||vec(b)|)=(vec(p).vec(c))/(|vec(p)||vec(c)|)` `rArr ((1)/(3)(x-2y+2z))/(sqrt(x^(2)+y^(2)+z^(2))(1)/(3)sqrt(1+4+4))=((1)/(5)(-4x-3z))/(sqrt(x^(2)+y^(2)+z^(2))(1)/(5)sqrt(16+9))=(y)/(sqrt(x^(2)+y^(2)+z^(2))sqrt(1))` `rArr (x-2y+2z)/(3sqrt(x^(2)+y^(2)+z^(2)))=(-4x-3z)/(5sqrt(x^(2)+y^(2)+z^(2)))=(y)/(sqrt(x^(2)+y^(2)+z^(2)))` `rArr (x-2y+2z)/(3)=(-4x-3z)/(5)=y` `:. 5(x-2y+2z)=-3(4x+3z)=15Y` `:. 5x-10y+10z=15y and -12x-9z=15y` `rArr 5x-25y+10z=0 and -12x-15y-9z=0` `rArr x-5y+2z=0 and 4x+5y+3z=0` `x-5y+2z=0` `4x+5y+3z=0` `|(x,y,z),(1,-5,2),(4,5,3)|=(x)/(-15-10)=(y)/(8-3)=(z)/(5+20)` `(x)/(-25)=(y)/(5)=(z)/(25)` `(x)/(-5)=(y)/(1)=(z)/(5)=k`(let) `:. x=-5k, y=k, z=5k` Now, `x^(2)+y^(2)+z^(2)=51` `:. (-5k)^(2)+k^(2)+(5k)^(2)=51` `rArr 25k^(2)+k^(2)+25k^(2)=51` `rArr 51k^(2)=51` `:. k=pm1` When, k=1, then `x=-5, y=1, z=5` `and vec(p)=5hat(i)+hat(j)+5hat(k)` when k=-1 , then x=5, y=-1, z=-5 `and vec(p)=5hat(i)-hat(j)-5hat(k)` |
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| 43. |
Evalute the following integrals int (1)/(sqrt(5x - 6- x^(2)))dx |
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| 44. |
If ""^(n)C_(3)=10, then n is |
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| 45. |
Ifalpha, beta are the roots of the equationx^(2) + x + 1 = 0 then prove thatalpha^(4) + beta^(4) + alpha^(-1) beta^(-1) = 0 . |
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| 46. |
If radii of two circles are 4 and 3 and distance between centres is sqrt37, then angle between the circles is |
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Answer» `30^@` |
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| 47. |
Find the sum of all five digited numbers that can be formed using the digits 1, 2, 3, 7, 9. |
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| 48. |
1+(1)/(3.2^(2))+(1)/(5.2^(4))+(1)/(7.2^(6))+....= |
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Answer» 1 |
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| 49. |
If a + b + c = 0, then the equation 3ax^(2) + 2bx + c = 0 has, in the interval (0, 1) |
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Answer» at leastone ROOT |
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| 50. |
In thegridshownbelow, eachsmallsquarehasa side lengthof 1 unit. Intheshadedregion , eachvertex lieson avertexof a small square. Whatis the area, in squareunits , of theshaded region ? |
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Answer» 35 |
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