Question

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

(a) ${45}^o$ (b) ${60}^o$ (c) ${90}^o$ (a) ${180}^o$

Answer 1

Given, $sinA=cosB\Rightarrow sinA=sin({90}^o-B)\Rightarrow A={90}^o-B\Rightarrow A+B={90}^o$