Step 1:
Simplify the integrand using the trigonometric identity for \( \sin 2x \):
\[
\int \sqrt{1 + \sin 2x} \, dx = \int \left( \sin x - \cos x + C \right) \, dx.
\]
Step 2:
This integral can now be solved directly:
\[
\int \left( \sin x - \cos x \right) \, dx = \sin x - \cos x + C.
\]