The value of sin sin\(\frac{5\pi}6\) is \(\frac 12\)
∴ The question becomes sin-1\((\frac 12)\)

The range of principal value of sin–1 is \([\frac{-\pi}2,\frac{\pi}2]
\) and sin\((\frac{\pi}6)=\frac 12\)
Therefore, the value of \(sin^{-1}(sin \frac{5\pi}6)\) is \(\frac{\pi}6.\)