Question

If tan A = cot B where A and B. are acute angles, prove that A + B = 90°.

Answer 1

Given that tan A = cot B 

⇒ cot (90° – A) = cot B [∵ tan θ = cot (90 – θ)] 

⇒ 90° – A = B 

⇒ A + B = 90°