Mathematics - Online Test

Q1. Which of the following is not possible ?
Answer : Option A
Explaination / Solution:

he value of cosθ  lies between - 1 and 1 

But when t=2 the value of   cosθ=1+t21t2,t0 is  which is more than 1 , so it is not possible.


Q2.  is equal to
Answer : Option D
Explaination / Solution:



Q3. A 3 × 3 matrix P is such that, P3 = P. Then the eigenvalues of P are
Answer : Option D
Explaination / Solution:



Q4.  to n terms is equal to
Answer : Option D
Explaination / Solution:

When n = 1 we get 3/4, and the subsequent terms when n is replaced by 2,3,4...

Q5. A fair coin is tossed a fixed number of times. If the probability of getting 4 heads is equal to the probability of getting 7 heads, then the probability of getting 2 heads is
Answer : Option D
Explaination / Solution:
No Explaination.


Q6. The foot of perpendicular from (α,β,γ) on Y axis is
Answer : Option C
Explaination / Solution:

Let P() be the point and Q (0,b,0) be any point on Y axis.

drs of PQ=(

drs of y axis (0,b,0)

Since PQ perpendicular to y axis.hence a1a2+b1b2+c1c2=0


hence the foot of perpendicular will be 


Q7.
Answer : Option D
Explaination / Solution:

The diagonal elements of a skew – symmetric matrix is always zero and the elements aij= - aji

Q8. The number of all odd divisors of 3600 is
Answer : Option B
Explaination / Solution:

To get the odd factors we will get rid of 2's

We will make the selection from only 3's and 5's 

Number of ways 3 can be selected from a lot of two 3's= 3 ways ( one 3,two 3's or three 3's)

Number of ways 5 can be selected from a lot of two 5's= 3 ways ( one 5,two 5's or three 5's)

Therefore  the number of odd factors is 3600= 3 X 3 =9


Q9. In vector form, if  is the angle between the two planes  then
Answer : Option B
Explaination / Solution:

In vector form, if  is the angle between the two planes  then, cosine of the angle between these two lines is given by :  

Q10.

Forming a differential equation representing the given family of curves by eliminating arbitrary constants a and b from  yields the differential equation


Answer : Option A
Explaination / Solution:

2yy=2xyy=xyy′′+y2+1=0