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. |
Show that the three lines with direction cosines (12)/(13),(-3)/(13),(-4)/(13),(12)/(13),(3)/(13),(-4)/(13),(12)/(13) are mutually perpendicular. |
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| 3. |
The product of the perpendicular from the foci on any tangent to the hyperbolax^(2) //a^(2) -y^(2) //b^(2) =1is |
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| 4. |
If P(A)=3/5 and P(B)=1/5 find P(A cap B), where A and B are independent events. |
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| 5. |
The probability that a boy will get a scholarship is 0.7 and that another boy will get is 0.8. What is the probability that atleast one them will get scholarship. |
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| 6. |
If alpha, beta are the eccentric angles of the extremities of a focal chord of the ellipse x^(2)/16+y^(2)/9, " then "tan""alpha/2tan""beta/2= |
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Answer» `(SQRT(5)+4)/(sqrt(5)-4)` |
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| 7. |
Let AP(a:d) denote the set of the all terms of an inginate arithmetic progression with first term a and common difference d gt 0 if AP (I,3)cap AP(2,5)capAP(3,7)=AP(a,d) then a+d equals........... |
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Answer» Now, LET `m^th` term of first progression and `n^th` term of progression `AP(2:5)=2+(n-1)6=5n-3` .....(ii) and `r^th` term of THIRD progression `AP(3:7)` `3+(r-1)7=7r-4` ........(iii) are equal Then `3m-2=5n-3=7r-4` Now, for `AP(1,3)capAP(2,5)capAP(3,7)`, the common terms of first and second PROGRESSIONS , `m=(5n-1)/(3)rArr n=2,5,11`,.........and the common tems of second and the third progressions. `r=(5n+1)/(7)rArrn=4,11`,...... Now the first common term of first, second and third progressions (when `n=11`), so `a=2+(11-1)6=52 ` and `d=LCM (3,5,7)=1-5` So, `AP(1,3)capAP(2:5)capAP(3:7)=AP(52:105)` So, `a=52and d=105 rArr a+d=157.00` |
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| 8. |
Two objects at the points P and Q subtend an angle of 30^(@) at a point A. Lengths AR = 20 m and AS = 10 m are measured from A at right angles to AP and AQ respectively. If PQ subtends equal angle of 30^(@), at R and S, then length of PQ is |
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Answer» `SQRT(300 - 200 sqrt(3))` |
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| 10. |
Let bar z+b bar z= c, b ne 0 be a line in the complex plane where bar b |
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Answer» SOLUTION :LetQ be `z_2` and its reflection be the p `(z_1)` in the given line . If O(z) be any point on the given line then by definition OR is right bisector of QP. `therefore ""Op=OQ or |z-z_1|=|z-z_2|` `rArr|z-z_1|^2=|z-z_2|^2` `rArr(z-z_1)(barz-barz_1)=(z - z_2)(barz-barz_2)` `rArr(barz_1-barz_2)+bar z(z_1 -z_2)=z_1 bar z_1- z_2barz_2` Comparing with given line `zbarb + bar ZB = C` `(barz_1-barz_2)/(BARB)=(z_1-z_2)/(B)=(z_1barz_1-z_2barz_2)/c=lambda` `(barz_1-barz_2)/(lambda)=bar b ,(z_1-z_2)/(lambda)b,(z_1barz_1-z_2 barz_2)/(lambda)c ......(i) ` `therefore barz_1 b+z_2barb=barz_1((z_1-z_2)/(lambda))+z_2((barz_1-barz_2)/(lambda))` `=(z_1barz_1-z_2barz_2)/(lambda)=c """[from Eq. (i)]"` |
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| 11. |
Find the number of 4 - digit telephone numbers that can be formed using the digits 1,2,3,4,5,6 with atleast one digit repeated. |
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| 12. |
On Z ** defined by a**b = a+b+1 . Is ** associative ? Find identity element and inverse if it exists. |
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| 13. |
If A and B are mutually exclusive and exhaustive events with P(A)=(2)/(3)P(B) then odds in favour of B are |
| Answer» ANSWER :D | |
| 14. |
Assume that in a family, each child is equally likely to be a boy or a girl. A family with three children is chosen at random. The probability that the eldest child is a girl given that the family has atleast one girl is ……….. |
| Answer» Answer :D | |
| 16. |
In what ratio should a given line be divided into 2 parts so that the rectangle contained by them is maximum ? |
| Answer» Answer :A | |
| 17. |
If (x_(1)-x_(2))^(2) + (y_(1)-y_(2))^(2) =a^(2), (x_(2)-x_(3))^(2) + (y_(2)-y_(3))^(2) = b^(2), (x_(3)-x_(1))^(2)(y_(3)-y_(1))^(2) =c^(2) and |{:(x_(1),y_(1),1),(x_(2),y_(2),1),(x_(3),y_(3),1):}|^(2) = (a+b+c)(b+c-a)(c+a-b)(a+b-c) then the value of lambda is: |
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Answer» `rArr 4LAMBDA Delta^(2) = 16 s(s-a) (s-b)(s-c)` `rArr 4lambda Delta^(2) = 16 Delta^(2)` `rArr 4lambda = 16 rArr lambda =4` |
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| 18. |
Probability of happening of an event in an experiment is 0.4 . The probability of happening of the event atleast once , if the experiment is repeated 3 times under similar condition is |
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Answer» `(1)/(16)` |
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| 19. |
Iff(x)[ log_(e)x+ sqrt({log_(e)x}), x lt 1, where [.]and f{.} denotethefreatestfunction and the fractional part function respectively , then |
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Answer» F(X)is continuousbut NON- DIFFERENTIABLE at x=e |
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| 20. |
Matrices of any order can be added. |
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Answer» Solution :FALSE Two matrices are ADDED, if they are of the same ORDER. |
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| 21. |
An unbiased die is tossed 6 times. The mean of number odd numbers is |
| Answer» Answer :A | |
| 22. |
Prove the following overset(1)underset(0)int sin^(-1)x dx=(pi)/(2)-1 |
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| 23. |
Find (dy)/(dx) when x and y are connected by the relation given: (x^(2) + y^(2))^(2)= xy |
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| 24. |
If the sum of the surface areas of cube and a sphere is constant, what is the ratio of an edge of the cube to the diameter of the sphere, when the sum of their volumes is minimum ? |
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| 25. |
In the matrix A=[(2,5,19,-7),(35,-2,(5)/(2),12),(sqrt(3),1,-5,17)], write: (i) The order of the matrix, (ii) The number of elements, (iii) Write the elements a_(13), a_(21), a_(33), a_(24), a_(23). |
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| 26. |
inte^x(tanx+Insecx)dx |
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Answer» Solution :`inte^x(tanx+Insecx)dx` =`inte^xtanxdx+ inte^xInsecxdx` INTEGRATING by PARTS) =`inte^xtanxdx+e^xInsecx-inte^xtanxdx` =`e^xIn(secx)+C` |
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| 27. |
A company manufactures two articles x and y. There are three departments through which these articles are processed. (i) welding (ii) assembly and (iii) colouring. The production of each article X requires 2 hours in welding, 3 hours in assembly and 1 hour in colouring and that of each unit of Y requires 3 hours in welding, 2 hours in assembling and 1 hours in colouring. The maximum capacity of welding departmentis 1500 hours, assembly department is 1500 hours and colouring department is 550 hours in each month. IF the profit is Rs. 1000 for each unit of x and Rs. 1200 for each unit of y, machines. How many machines of each type should be buy to maximise the daily out put ? |
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| 29. |
DeltaABC is given in adjacent diagram. P is mid-point of AC and Q is foot of perpendicular from origin tp AB {:(,"Column-I",,"Column-II",,"Column-III",),((I),squareAQOP "is square",(i),P=((b)/(2),(b)/(2)),(P),"OQ=OP",),((II),DeltaOPQ "is an equilateral traingle",(ii),Q=(-(b)/(2),(b)/(2)),(Q),"AQ=AP",),((III),"OQ=QB",(iii),"OP=PC",(R),OP=(b)/sqrt(2),),((IV),AQ=QB",(iv),PC=OC,(R),OQ=b,):} Which of the following is incorrect : |
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Answer» <P>`(II)(ii)P` |
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| 30. |
DeltaABC is given in adjacent diagram. P is mid-point of AC and Q is foot of perpendicular from origin tp AB {:(,"Column-I",,"Column-II",,"Column-III",),((I),squareAQOP "is square",(i),P=((b)/(2),(b)/(2)),(P),"OQ=OP",),((II),DeltaOPQ "is an equilateral traingle",(ii),Q=(-(b)/(2),(b)/(2)),(Q),"AQ=AP",),((III),"OQ=QB",(iii),"OP=PC",(R),OP=(b)/sqrt(2),),((IV),AQ=QB",(iv),PC=OC,(R),OQ=b,):} Which of the following is correct : |
| Answer» Answer :C | |
| 31. |
DeltaABC is given in adjacent diagram. P is mid-point of AC and Q is foot of perpendicular from origin tp AB {:(,"Column-I",,"Column-II",,"Column-III",),((I),squareAQOP "is square",(i),P=((b)/(2),(b)/(2)),(P),"OQ=OP",),((II),DeltaOPQ "is an equilateral traingle",(ii),Q=(-(b)/(2),(b)/(2)),(Q),"AQ=AP",),((III),"OQ=QB",(iii),"OP=PC",(R),OP=(b)/sqrt(2),),((IV),AQ=QB",(iv),PC=OC,(R),OQ=b,):} Which of the following is incorrect : |
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Answer» `(IV)(iiii)R` |
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| 32. |
Find the shortest distance between the lines (x)/(5)= (y-2)/(2) =(3-z)/(-3) and (x+3)/(5)=(1-y)/(-2)=(z+4)/(3) |
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| 33. |
lim_(x rarr oo) (sqrt(a^(2) x^(2) + bx + c) - ax) = |
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Answer» `(B)/(2A)` |
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| 35. |
Let 'P' be an interior point of Delta ABC. If angle A=45^(@), angle B=60^(@) and angle C=75^(@). If X=area of Delta PBC,Y= area of Delta PAC and Z = area of Delta PAB, then which of the following ratios is/are true ? |
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Answer» If P is the centroid, then X : Y : Z is 1 : 1 : 1 Using properties of median, we have `Delta PBC = Delta PCA = Delta PAB` `therefore Delta PBC : Delta PCA : Delta PAB = 1:1:1` (B) `Delta PBC : Delta PCA : Delta PAB` `=(1)/(2)ar : (1)/(2)br : (1)/(2)cr` `= a:b:c` `= sin 45^(@): sin 60^(@): sin 75^(@)=2 : sqrt(6):(sqrt(3)+1)` (c ) `Delta PBC : Delta PCA : Delta PAB` `=(1)/(2)a(2R COS B cos C) : (1)/(2)b(2 R cos C cos A) : (1)/(2)c(2R cos A cos B)` = sin A cos B cos C : sin B cos C cos A : sin C cos A cos B `= tan 45^(@) : tan 60^(@) : tan 75^(@)` `= 1: sqrt(3):(2+sqrt(3))` (d) `Delta PBC : Delta PCA : Delta PAB` `=(1)/(2)R^(2)sin 2A : (1)/(2)R^(2)sin 2B(1)/(2)R^(2)sin 2C` `= sin 2A : sin 2B : sin 2C` `= sin 90^(@) : sin 120^(@) : sin 150^(@)` `= 2 : sqrt(3):1` |
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| 36. |
Which of the following statements is not true about f(x) = 1+x+ x^(2)/(2!) +...+ x^(2n)/ (2n!)(n gt 1) |
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Answer» the MINIMUM value of f(X) is POSITIVE |
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| 37. |
A variable line L is drawn through O(0,0) to meet the line L_(1) " and " L_(2) given by y-x-10 =0 and y-x-20=0 at Points A and B, respectively. Locus of P, if OP^(2) = OA xx OB, is |
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Answer» `(y-x)^(2) = 100` `"or " (r "sin" theta - r" cos" theta)^(2) = 200` Hence, the locus is `(y-x)^(2) = 200`. |
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| 38. |
With usual notions, prove that in a triangle ABC, cot (A)/(2)+cot (B)/(2)+cot(C )/(2)= (s)/(r ). |
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| 39. |
cot{ (2019pi)/(2) - ( cosec^(-1) (5)/(3) + tan^(-1)"" (2)/(3) ) } = ..... |
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Answer» `(17)/(6)` |
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| 40. |
Resolve (3x^(3)-2x^(2)-1)/(x^(4)+x^(2)+1) into partial fractions. |
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| 41. |
The vector equations of two lines L_(1) and L_(2) are respectively r=17i-9k+lamda(3i+j+5k) and r=15i-8j+k+mu(4i+3j). Then the correct statement(s) is/are: |
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Answer» `(-11,11,1)` is the point of intersection of `L_(1)` and `L_(2)` |
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| 42. |
Statement I The triangle so obtained is an equilateral triangle. Statement II If roots of the equations be tan A, tan B and tanC then tan A + tanB+tanC=3sqrt (3) |
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| 43. |
For theta in[ 0, 2pi] , consider the followingstatement : p : sqrt(1 - cos (2 theta)) = sqrt(2) | sin theta| q: sqrt(1 - cos (2 theta)) + sqrt(2) sin theta = 0 " if " pi le theta le 2 pi Then truth values of p and q are respectively: |
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Answer» T, T |
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| 44. |
Evaluate the definite integrals int_(0)^(pi/4)tanxdx |
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| 45. |
If bar(a),bar(b) and bar( c ) are not coplanar then (bar(a)+bar(b)+bar( c ))*[(bar(a)+bar(b)) times (bar( a )+bar(c))] = …………… |
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Answer» `[(BAR(a),bar(B),bar( C ))]` |
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| 46. |
Let A = { 1, 2, 3, …….n} , if a_(i) is the minimum element of the set A, (where A , denotes the subset of A containingexactly three elements) and X denotes the set of A_(i)'s , then evalute sum_(A_(i)inX) a |
| Answer» SOLUTION :`""^(n+1)C_(4)` | |
| 47. |
Three point A, B and C with position vectors a_(1)=3hati-2hatj-hatk, a_(2)=hati+3hatj+4hatk and a_(3)=2hati+hatj-2hatk relative to an origin O. The distance of A from the plane OBC is (magnitude) |
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Answer» 5 i.e., `a_(1)*(a_(2)xxa_(3))=0` The distanceof A from the plane `OBC = |(a_(1)*(a_(2)xxa_(3)))/(|a_(2)xxa_(3)|)|` `a_(2)xxa_(3) = -10hati + 10 hatj - 5hatk` `rArr| a_(2) xx a_(3)|=15` `THEREFORE ` DISTANCE ` = (1)/(15)||(3,-2,-1),(1,3,4),(2,1,-2)||=3` |
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| 48. |
Using the binomial theorem show that 1^(99) + 2^(99) +3^(99) + 4^(99) + 5^(99) is divisible by 3 and 5 so that it is actually divisible by 15. |
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Answer» SOLUTION :From EQN. (1) above, it is clear that each term within the 1st brackets is divisible by 3 and the TERMS in the 2nd bracket is divisible by 99 and HENCE divisible by 3. therefore Each term in eqn.(1) is divisible by 3 and 5 , it is divisible by `3xx5` = 15. |
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| 49. |
The statement ~p vv q is equivalent is |
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Answer» <P>`p RARR Q` |
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| 50. |
Fleshy buds produced in the axil of leaves, which grow to form new plants when shed and fall on ground, are called |
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Answer» bulbs |
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