Evaluate sin⁻¹(sin 3)

Evaluate \( \sin^{-1}(\sin 3) \)

Step-by-Step Solution

We need to evaluate:

\[ \sin^{-1}(\sin 3) \]

Step 1: Principal value range

The principal value range of \( \sin^{-1}x \) is:

\[ \left[-\frac{\pi}{2}, \frac{\pi}{2}\right] \]

Step 2: Check the angle

Since \( 3 \notin \left[-\frac{\pi}{2}, \frac{\pi}{2}\right] \), we cannot directly write:

\[ \sin^{-1}(\sin 3) \neq 3 \]

Step 3: Use identity

\[ \sin(\pi – x) = \sin x \]

\[ \sin(3) = \sin(\pi – 3) \]

Now \( \pi – 3 \in \left[-\frac{\pi}{2}, \frac{\pi}{2}\right] \)

Step 4: Apply inverse sine

\[ \sin^{-1}(\sin 3) = \sin^{-1}(\sin(\pi – 3)) = \pi – 3 \]

Final Answer

\[ \boxed{\pi – 3} \]

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