Mathematics - Online Test

Q1. The area bounded by the curve y =x, the x – axis and the ordinates x = 1 and x = -1 is given by
Answer : Option B
Explaination / Solution:



Q2. The scalar product of two nonzero vectors  is defined as
Answer : Option B
Explaination / Solution:

The scalar product of two nonzero vectors  is defined as : 

Q3. cosx(1+sinx)(2+sinx)dx=
Answer : Option D
Explaination / Solution:



Q4. The relation is valid for
Answer : Option C
Explaination / Solution:

The relation is true for all real values of x greater than or equal to 1.

Q5. The line y = c is a tangent to the parabola x= y - 1 if c is equal to
Answer : Option C
Explaination / Solution:

putting the value y=c into parabola,we get

x2=c-1

or x2-(c-1)=0

here discriminat=

line y=c is tangent when discriminant is equal to 0.

putting disriminant =0 we get c=1.

(0, c) will be a point on the parabola. 


Q6. The general value of θ satisfying the equation  is
Answer : Option B
Explaination / Solution:



Q7.

 is equal to


Answer : Option D
Explaination / Solution:

 
Q8.  upto n terms is equal to
Answer : Option B
Explaination / Solution:

Replace n = 1 we have 1/2. When n = 2 we have 1/2+1/6=2/3,( by the principle of mathematical induction when n = 1 we need to take one term from LHS. and for n = 2 we need to take the sum of two terms from the LHS. .....)

Q9. In a certain town , 40% persons have brown hair , 25% have brown eyes , and 15% have both. If a person selected at random has brown hair , the chance that a person selected at random with brown hair is with brown eyes
Answer : Option C
Explaination / Solution:
No Explaination.


Q10. The centre of the sphere , which passes through ( a , 0 , 0 ) , ( 0 , b , 0 ) ( 0 , 0 , c ) and ( 0 , 0 ,0 ) is ? where abc ≠ 0
Answer : Option D
Explaination / Solution:

General equation of the sphere is ---------------------1)

Since 1) passes through the point (0,0,0) using this in 1) we get d=0

Similarly 1) passes through ( a , 0 , 0 ) , ( 0 , b , 0 ) ( 0 , 0 , c ) using these values in 1)


But as abc0  So , a 0 ,b 0 ,c 0

So from above equations , we have a =  - 2g , b= - 2f , c = -2h

 centre is (-f ,-g , -h) = ( a/2 , b/2 , c/2 )