Question

value of cos^-1(3pie/2)

Answer 1

$\huge \mathfrak \purple{answer}$

$\sf \huge \implies \: {cos}^{ - 1} (cos \: \frac{3\pi}{2} )$

$\sf \huge \implies \: {cos}^{ - 1} (cos(2\pi - \frac{\pi}{2} )) \\ \\ \sf \huge \implies \: {cos}^{ - 1} (cos \: \frac{\pi}{2} ) \\ \\ \sf \huge \red{ \implies \: \frac{\pi}{2}}$