Question

If cos (90⁰

-A)=0, then Sin (A+B)=

A) 0

B) 2

C) 3

D) None of the above​

Answer 1

$\cos(90 - a) = 0 \\ \cos(90 - a) = \cos(90) \\ 90 - a = 90 \\ a = 0$

1. $\sin(a + b) \\ = \sin(90 + b) \\ Thus, (d) is \: the \: answer. \:$

Hope this helps.

Thanks.