Question

If A and B are acute angles such that sin A = cos B then (A + B) = ?

Options

• 30°

• 45°

• 60°

• 90°

Answer 1

90°

Explanation:

sin A = cos B

⇒ sin A = sin (90° – B) 

⇒ A = 90° – B

⇒ A + B = 90°