Question

Pls solve question no 12 and tell which option is correct

Answer 1

Step-by-step explanation:

Option D is correct.

Given that cos(a+b)=0

So, cos(a+b) =cos 90°

=(a+b) =90°

=a=90°-b

Now

=Sin(a-b)

=Put value of a

=Sin(90°-b-b)

=Sin(90°-2b)

=cos2b