Mathematics - Online Test

Q1. If the angles of a triangle be in the ratio 1 : 4 : 5, then the ratio of the greatest side to the smallest side is
Answer : Option A
Explaination / Solution:



Q2.

The area of the figure bounded by the curve , the x – axis and the straight line x = e is


Answer : Option D
Explaination / Solution:

Required area :
$ = - = 1

Q3. The radius of the sphere through the points ( 4 ,3 , 0 ) , ( 0 , 4 , 3 ) ,( 0 , 5 , 0 ) and ( 4 , 0 , 3 ) is
Answer : Option A
Explaination / Solution:

we know that general equation of sphere is  

since sphere passing through the points  ( 4 ,3 , 0 ) , ( 0 , 4 , 3 ) ,( 0 , 5 , 0 ) and ( 4 , 0 , 3 ) so putting these values one by one in given equation , we get

16+ 9+ 8g + 6f + c=0    =>8g +6f +c = -25  -------------1)

16 +9 +8f +6h +c=0    =>8f + 6h +c= -25   -----------2)

25 + 10f +c  = 0       -----------------------3)

16+ 9+ 8g + 6h +c=0    =>8g +6h +c= -25  -------------4)

by 2) - 4 ) we have  f = g

using this in 1) we have 16f +c = -25 -------5)

Now solving 3) and 5) we get f=0 

using value of f  we have g= 0 , h= 0 , c= -25

Now radius =  =  =5


Q4. The order of [x y z] is
Answer : Option A
Explaination / Solution:

 [A]1 x 1 . ( where ; matrix A denotes the product of three given matrices.)

Q5. The function f(x) =  is
Answer : Option A
Explaination / Solution:

f(x)=ddx(tan1x)
Therefore , f is strictly increasing  on R

Q6. If A and B are two sets , then A∪B=A∩BA∪⁡B=A∩⁡B iff
Answer : Option C
Explaination / Solution:



Q7. If  are non real complex numbers such that  are real numbers , then
Answer : Option A
Explaination / Solution:



Q8. The maximum value of F(x) = x3 – 9x2 + 24x + 5 in the interval [1, 6] is
Answer : Option C
Explaination / Solution:



Q9. If A ,B andC be the three square matrices such that A = B + C , then Det A is equal to
Answer : Option C
Explaination / Solution:

Because , if A=B+C then |A|=|B+C|

Q10. The term containing  in the expansion of  is
Answer : Option B
Explaination / Solution: