Concept:
• The Range (Principal Value Branch) of \( f(x) = \sin^{-1}x \) is \( [-\frac{\pi}{2}, \frac{\pi}{2}] \).
• This means for any defined \( x \), \( -\frac{\pi}{2} \leq \sin^{-1}x \leq \frac{\pi}{2} \).
Step 1: Isolate the inverse trigonometric term
Given the equation:
\[ \sin^{-1}x + \pi = y \]
Subtract \( \pi \) from both sides to get:
\[ \sin^{-1}x = y - \pi \]
Step 2: Apply the standard range constraint
We know the bounds for the arcsine function:
\[ -\frac{\pi}{2} \leq \sin^{-1}x \leq \frac{\pi}{2} \]
Step 3: Substitute and solve the inequality for \( y \)
Replace \( \sin^{-1}x \) with \( y - \pi \):
\[ -\frac{\pi}{2} \leq y - \pi \leq \frac{\pi}{2} \]
Step 4: Add \( \pi \) to all parts of the inequality
\[ \pi - \frac{\pi}{2} \leq y \leq \pi + \frac{\pi}{2} \]
\[ \frac{\pi}{2} \leq y \leq \frac{3\pi}{2} \]