Concept:
For large \( x \), bounded functions like \( \sin x, \cos x \) become negligible compared to \( x \).
Step 1: Approximate numerator.
\[
x - \sin x \approx x
\]
Step 2: Approximate denominator.
\[
x + \cos^2 x \approx x
\]
Step 3: Simplify.
\[
\sqrt{\frac{x}{x}} = 1
\]