Question

Simplify $\frac{\cos {37}^{\circ }}{\sin {53}^{\circ }}\times \frac{\sin {18}^{\circ }}{\cos {72}^{\circ }}$

Answer 1

$\frac{\cos 37°}{\sin 53°}\times \frac{\sin 18°}{\cos 72°}=\frac{\cos (90°-53°)}{\sin 53°}\times \frac{\sin (90°-72°)}{\cos 72°}$

$\Rightarrow \frac{\sin 53°}{\sin 53°}\times \frac{\cos 72°}{\cos 72°}=1$

Hence, the answer is $1.$