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. |
Solution set of sqrt(3 - x) = - x^(2) - x - 1 , x in R is |
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Answer» `(- 1 , INFTY)` |
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| 2. |
Consider a plane prod:vecr*(2hati+hatj-hatk)=5, a line L_(1): vecr=(3hati-hatj+2hatk)+lambda(2hati-3hatj-hatk)and a point a(3, -4, 1)*L_(2)is a line passing through A intersecting L_(1) and parallel to plane prod. Q.Line L_(1) intersects plane prod at Q and xy-plane at R the volume of tetrahedron OAQR is : (where 'O' is origin) |
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Answer» 0 |
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| 3. |
Show that the area under the curve y = sin xandy = sin 2x between x = 0 and x = ( pi)/( 3)andx -axis are as 2:3 |
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| 4. |
Consider a plane prod:vecr*(2hati+hatj-hatk)=5, a line L_(1): vecr=(3hati-hatj+2hatk)+lambda(2hati-3hatj-hatk)and a point a(3, -4, 1)*L_(2)is a line passing through A intersecting L_(1) and parallel to plane prod. Q.Plane containing L_(1) and L_(2) is : |
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Answer» PARALLEL to yz-plane |
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| 5. |
Consider a plane prod:vecr*(2hati+hatj-hatk)=5, a line L_(1): vecr=(3hati-hatj+2hatk)+lambda(2hati-3hatj-hatk)and a point a(3, -4, 1)*L_(2)is a line passing through A intersecting L_(1) and parallel to plane prod. Q.Equation of L_(2) is : |
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Answer» `vecr=(1+LAMBDA)hati+(2-3lambda)hatj+(1-lambda)hatk:lambda in R` |
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| 6. |
A box contains N coins, m of which are fair and the rest are biased. The probability of getting a head when a fair coin is tossed is 1/2, while it is 2/3 when a biased coin is tossed. A coin is drawn from the box at random and is tossed twice. The first time it shows heads and the second time it shows tails. The probability that the coin drawn is fair is |
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Answer» `(9M)/(8N+m)` |
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| 7. |
The solution of 2y cos y^(2) (dy)/(dx) - (2)/(x +1) sin y^(2) = (x + 1)^(3) is |
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Answer» `SIN y^(2) = (x + 1)^(2) [(x + 1)^(2) + c]` |
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| 8. |
int(dx)/(1-sinx+cosx)= |
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Answer» `LOG|(TAN((X)/(2))+1)|+C` |
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| 9. |
The locus of the points of intersection of tangents to the hyperbolax^(2) - y^(2) =a^(2) which include an angle of45^(@)is |
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Answer» ` (X^(2) + y^(2) )^(2) =4A^(2) (x^(2) + y^(2) +a^(2))` |
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| 10. |
Prove that the function f: N to Y defined by f(x) = x^(2), where y = {y : y = x^(2) , x in N} is invertible. Also write the inverse of f(x). |
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| 11. |
Let (2x^(2)+3x+4)^(10)=sum_(r=0)^(20)a_(r )x^(r ), then the value of (a_(7))/(a_(13)) is |
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Answer» `6` Replacing `x` by `(2)/(x)`, we get `((8)/(x^(2))+(6)/(x)+4)^(10)=sum_(r=0)^(20)a_(r )((2)/(x))^(r )` `implies2^(10)(2x^(2)+3x+4)^(10)=sum_(r=0)^(20)a_(r )2^(r )x^(20-r)` `impliessum_(r=0)^(20)a_(r )x^(r )=sum_(r=0)^(20)a_(r )2^(r-10)x^(20-r)` Comparing coefficient `x^(7)` both SIDES , we get `a_(7)=a_(13)xx2^(3)`. |
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| 12. |
If x_(1) and x_(2) are the roots of the equation sqrt(2010)x^(log_(2010^(x))) = x^(2), then find the cyphers at the end of the product (x_(1)x_(2)). |
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| 13. |
Show that the tangent to the curve x^(2)(x^(2)-1)=cy^(2)c, c is a constant, P(x, y) cuts the y - axis at (0, y^(3)). |
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| 14. |
If z=(x+iy) and if the point P in the Argarand plane represent z, then desrcibe geo-metrically the locus of P satispfying the equation. |z|^(2) 4 Re (z+2) |
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Answer» a straight LINE |
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| 15. |
The point of intersection of the tangents at t_(1) and t_(2) to the parabola y^(2)=12x is |
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Answer» `[2t_(1)t_(2),2(t_(1)-t_(2))]` |
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| 16. |
Find the values of x, y, z if the matrixA=[(0, 2y,z),(x,y,-z),(x,-y,z)] satisfy the equation A'A=I. |
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| 17. |
Using the letters of the word 'RAM' 5 letter words are formed in such a way R, A, M each appears atleast once in each word. If a word is selected from these words find the probability that A appears exactly once in the selected word. |
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| 19. |
If maximum value of int _(0)^(1) (f (x ))^(2) dx under the condition -1 le f (x) le 1, int _(0)^(1) f (x) dx -0 is (p)/(q) (where p and q are relatively prime positive integers). Find p+q. |
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| 20. |
Which of the given values of x and y make the following pair of matrices equal [(3x+7,5),(y+1,2-3x)],[(0,y-2),(8,4)]a) x= -(1)/(3), y=7b) Not possible to find c) y=7, x= -(2)/(3)d) x= -(1)/(3), y= -(2)/(3) |
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Answer» `x= -(1)/(3), y=7` |
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| 21. |
There are 10 intermediate stations on a railway line between two particular stations. The number of ways that a train can be made to stop at 3 of these intermediate stations so that no twoof these halting stations are consecutive is |
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Answer» 56 |
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| 22. |
Find the unit vectors perpendicular to the vectors. 2hati+3hatk, hati-2hatj |
Answer» SOLUTION : `|VECAXXVECB| = SQRT(36+9+16) = sqrt(61)` therefore `HATN = +-(vecaxxvecb)/|vecaxxvecb| = +-(6hati+3hatj-4hatk)/sqrt(61)`. |
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| 23. |
Integrate the following functions (logx)^2/x |
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Answer» SOLUTION :PUT logx = t Then DT = 1/x dx THEREFORE` int (logx)^2/x dx = int t^2 dt = t^3/3 +c` =`(logx)^3/3 +c` |
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| 24. |
If z_(1), z_(2), z_(3) are affixes of the vertices A, B and C respectively of a triangle ABC having centroid at G such that z = 0 is the mid point of AG, then |
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Answer» `z_(1)+z_(2)+z_(3)=0` |
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| 25. |
If (1+x -2x^2)^8 =1 -a_1x + a_2x^2+……+a_16x^16,then a_2+a_4+a_6+……+a_16= |
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Answer» 120 |
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| 26. |
If p is the length of the perpendicular from the origin to the line whose intercepts will the coordinate axes are (1)/(3) and (1)/(4) then the value of p is |
| Answer» Answer :D | |
| 27. |
If the probability distribution of a random variable X is given by |
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Answer» `3` |
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| 28. |
If x is real and k = (x^2 - x+1)/(x^2 + x +1) then |
| Answer» Answer :A | |
| 29. |
All of the following has the same set of unique prime factors EXCEPT: |
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Answer» 420 |
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| 30. |
Differentiate w.r.t.x the function (5x)^( 3 cos 2x) |
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| 31. |
Integrate the following functions ((x+1)(x+logx)^2)/x |
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Answer» Solution :`((x+1)(x+logx)^2)/x` `(1+1/x)(x+logx)^2` LET t = x+logx. Then DT = (1+1/x)DX therefore `int ((x+1)(x+logx)^2)/x dx = int t^2 dt` `t^3/3 +C = (x+logx)^3/3 +c` |
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| 32. |
Evaluate: int(dx)/((x-1)xsqrt(x^(2)-1) |
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Answer» Solution :`INT(dx)/((x-1)xsqrt(x^(2)-1)) ("put" x-1=1/t rArr dx=-1/t^(2)DT)` `rArr I=int(-1/t^(2)dt)/(1/2sqrt(1/t+1)^(2)-(1/t+1)-1) = int(-dt)/SQRT(-t^(2)+t+1) = int(-dt)/sqrt(sqrt(5)/(2))^(2)-(t-1/2)^(2)` `=-sin^(-1)(t-1/2)/(sqrt(5)/2) + C=-sin^(-1)(2t-1)/(sqrt(5))+C`, where `t=1/(x-1)` |
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| 33. |
A bag contains 3 white and black balls. A person draws 3 balls at random from it. He then drops 3 red balls in the bag and again draws out 3 balls at random. What is the chance that the later 3 balls will be of different colours. |
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| 34. |
Which of the following is/are redox reaction. |
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Answer» `KCl + K_(2) Cr_(2)O_(7) to con.H_(2)SO_(4) to CrO_(2)Cl_(2) +K_(2)SO_(4) +H_(2)O` |
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| 35. |
Evalute: int_(0)^(pi//2)(x sinx cosx)/(sin^(4)x+cos^(4)x)dx. Or, Eventuate: int_(0)^(4)(x+e^(2x))dx as the limit of a sum. |
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Answer» Or, `8+1/2(e^(8)-1)` |
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| 36. |
If a, b, c are real numbers in A.P., then the roots of ax^(2) +bx +c=0 are real for |
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Answer» all a and C |
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| 37. |
Which of the following is a null set |
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Answer» {0} |
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| 38. |
Compute the following: [[a,b],[-b,a]][[a,-b],[b,a]] |
| Answer» SOLUTION :`[[a,B],[-b,a]], [[a,-b],[b,a]]=[[a^2+b^2, -ab+ab],[-ab+ab, b^2+a^2]]=[[a^2+b^2, 0],[0, a^2+b^2]]` | |
| 39. |
Solve the following differential equations. (dy)/(dx)+(3x^(2))/(1+x^(3)) y=(1+x^(2))/(1+x^(3)) |
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| 40. |
20 persons A_1,A_2….A_(20), are sitting around a circle. In how many ways 7 persons out of them can be selected such that no two of the selected 7 are consecutive and A_1 must always be one among the selected 7. |
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| 41. |
Let z(x,y) =x^(3) - 3x^(2)y^(3), where x = se^(t), y =se^(-t), s, t in R. Find (del z)/(del s) and (del z)/(del t) |
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| 42. |
If a, b, c in N, the probability that a^(2)+b^(2)+c^(2) is divisible by 7 is (m)/(n) where m, n are relatively prime naturalnumbers, then m + n is equal to : |
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| 44. |
If (a-b)sin (theta+phi)=(a+b)sin(theta-phi) and a tan. (theta)/(2)-b tan.(phi)/(2)=c, then |
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Answer» `b tan PHI = a tan theta` `rArr (sin(theta+phi))/(sin(theta-phi))=(a+b)/(a-b)` `rArr (sin(theta + phi)+sin(theta-phi))/(sin(theta+phi)-sin(theta-phi))=(2A)/(2b)` `rArr (2sin theta cos phi)/(2 cos theta sin phi)=(a)/(b)=(tan theta)/(tan phi)=(a)/(b)` `rArr b tan theta = a tan phi` `therefore` (b) is TRUE `rArr (2a tan.(phi)/(2))/(1-"tan"^(2)(phi)/(2))=(2b tan.(theta)/(2))/(1-"tan"^(2)(theta)/(2))` `rArr (a((a tan.(theta)/(2)-c)/(b)))/(1-((a tan.(theta)/(2)-c)/(b))^(2))=(b tan.(theta)/(2))/(1-"tan"^(2)(theta)/(2))` `rArr ((a^(2)tan.(theta)/(2)-AC))/(b^(2)-(a^(2)"tan"^(2)(theta)/(2)+c^(2)-2ac tan.(theta)/(2)))` `=(tan.(tehta)/(2))/(1-"tan"^(2)(theta)/(2))` `rArr (a^(2)tan.(theta)/(2)-ac)(1-"tan"^(2)(theta)/(2))` `= b^(2) tan.(theta)/(2)-a^(2)"tan"^(3)(theta)/(2)-c^(2)tan.(theta)/(2)+2 ac "tan"^(2)(theta)/(2)` `= a^(2) tan.(theta)/(2)-ac - a^(2)"tan"^(3)(theta)/(2)+ac "tan"^(2)(theta)/(2)` `rArr b^(2) tan.(theta)/(2)-a^(2)"tan"^(3)(theta)/(2)-c^(2)tan.(thetA)/(2)+2 ac "tan"^(2)(thetA)/(2)` `rArr (a^(2)+c^(2)-b^(2))tan.(theta)/(2)=ac[1+ "tan"^(2)(thetA)/(2)]` `rArr (2 tan.(theta)/(2))/(1+ "Tan"^(2)(thetA)/(2))=(2ac)/(c^(2)+a^(2)-b^(2))` `rArr sin theta = (2ac)/(c^(2)+a^(2)-b^(2))` `rArr sin theta = (2ac)/(c^(2)+a^(2)-b^(2))` Similarly, `sin phi=(2bc)/(a^(2)-b^(2)-c^(2))` |
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| 45. |
Intergrate the following: intsin4x cos3xdx |
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Answer» SOLUTION :`intsin4x cos3xdx` =`1/2 int2sin4x .cos3xdx` =`1/2int(sin7x+sinx)DX` =`1/2{-(COS7X)/7-cosx}+C` =-1/14cos7x-1/2 cosx+C |
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| 46. |
If the quadratic equation 4^("sec"^(2)alpha).X^(2)+2x+(beta^(2)-beta+(1)/(2))=0 has real roots , then the value of cos^(2)alpha + cos^(-1)beta is |
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Answer» `(pi)/(3)` |
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| 47. |
D.c.s of a line segment AB are (-2)/(sqrt(17)),(3)/(sqrt(17)),(-2)/(sqrt(17)). If AB=sqrt(17)andA-=(3,-6,10), then co-ordinates of B will be |
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Answer» `(2,5,8)` |
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| 48. |
The sum of 10 terms of the series sqrt(2) + sqrt(6) + sqrt(18) + .... is |
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Answer» `121(SQRT(6) + sqrt(2)` |
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| 49. |
(""^(m)C_(0) +""^(m) C_(1) -^(m) C_(2)-^(m)C_(3)) + (""^(m) C_(4) + ^(m) C_(5) -^(m)C_(6)-^(m) C_(7))+... = 0 if and only if for some positive integer k, m is equal to |
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Answer» 4k `=^(m)C_(0) (cos theta)^(m) +^(m)C_(1)(costheta)^(m-1) (isin theta)` `+ C_(2)(costheta)^(m-1) (isin theta)^(2)+...+""^(m)C_(m)(isintheta)^(m)` `(cos m theta + isin m theta) = [""^(m)C_(0)(cos theta)^(m)-^(m)C_(2)(cos theta)^(m-2)CDOT sin ^(2) theta +""^(m)C_(4)(costheta)^(m-4)sin^(4) theta - ...] + i [""^(m)C_(1)(cos theta)^(m-1) sin theta -^(m) C_(3) (cos theta)^(m-3)sin^(3) theta +..]` [ using Demovire' s theromem] Comparing real and imaginary parts, we geta `cos mtheta = ^(m)(cos theta)^(m) -^(m) C_(2) (cos theta)^(m-2)sin^(2)theta+^(m)C_(4) (cos theta )^(m-4) sin ^(4) theta - ......(i)` `sin mtheta= ^(m) C_(1) (cos theta)^(m-1) cdot sintheta -^(m) C_(3)(cos theta)^(m-3 )cdot sin^(3) theta + ......(ii) ` On adding Eqs. (i) and (ii), we get `cos m theta + sin m theta = ^(m)C_(0)(costheta)^(m) + C_(1) (costheta)^(m-1)cdot sin theta -^(m) C_(2) (cos theta)^(m-2)sin ^(2) theta-^(m) C_(3)(cos)^(m-3)sin ^(3) theta` `+^(m)C_(4)(costheta)^(m-4)sin^(4)theta + ...sin (mtheta + pi/4)` `=(costheta)^(m){{:(""^(m)C_(0)+^(m)C_(1)tan theta-^(m)C_(2)tan^(2)theta -^(m)C_(3)tan^(3)),(+^(m)C_(4)tan^(4)theta + ^(m) C_(5)tan^(5) theta-...):}} ` Putting `theta=pi/4, sqrt(2)sin (((m+1)pi)/4)=1/2^(m//2)` `{{:((""^(m)C_(0) +^(m) C_(1)-^(m) C_(2)-^(m) C_(3))+(""^(m)C_(4)+^(m) C_(5)-^(m) C_(6)-^(m) C_(7))),(+...+(""^(m)C_(m-3)+^(m) C_(m-2)-^(m) C_(m-1)-^(m) C_(m)) ):}}` `because((""^(m)C_(0) +^(m) C_(1)-^(m) C_(2)-^(m) C_(3))+(""^(m)C_(4)+^(m) C_(5)-^(m) C_(6)-^(m) C_(7))` `therefore sin frac((m+1)pi)(4)=0 rArr ((m+1)pi)/4 = k pi` or `m=4k-1,AAkinI` |
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| 50. |
Find the area enclosed by the circle the ellpise x^(2)/a^(2) + y^(2)/b^(2) = 1 |
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