Step 1: Apply trigonometric substitution.
Use a substitution to simplify the integrand. The integral \( \int_0^{\frac{\pi}{2}} \frac{\sin x}{1 + \cos^2 x} \, dx \) can be solved by using standard integration techniques.
Step 2: Conclusion.
After performing the integration, the result is \( \frac{\pi}{4} \).
Final Answer:
\[
\boxed{\frac{\pi}{4}}
\]