Answer
$\frac{\pi}{4}$
Work Step by Step
Within the restricted interval ($-\frac{\pi}{2}\leq\theta\leq\frac{\pi}{2}$),
$\sin^{-1}(\sin\theta)=\theta$
Therefore, $\sin^{-1}(\sin\frac{\pi}{4})=\frac{\pi}{4}$
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