CBSE 11TH MATHEMATICS - Online Test

Answer : Option D
Explaination / Solution:

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

Answer : Option D
Explaination / Solution:
No Explaination.

Answer : Option C
Explaination / Solution:

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

drs of PQ=(α,β−b,γ)

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 (0,β,0)

Answer : Option B
Explaination / Solution:

wehave3600=24.32.52

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

Answer : Option B
Explaination / Solution:

i0=1,i1=i,i2=−1,i3=i2.i=−i

Now we can see for n=0,4,8....... the value of in = 1

For n=1,5,9....... the value of in =i

for n=2,6,10....... the value of in=-1 

for n=3,7,11....... the value of in = -i

similarly for all negative integers also n  takes any one value among 1 ,-1 , i ,-i

Answer : Option A
Explaination / Solution:

Answer : Option A
Explaination / Solution:

here value of x is not possible so A is a null set.

Answer : Option B
Explaination / Solution:

Answer : Option A
Explaination / Solution:

Answer : Option D
Explaination / Solution: