Use Identities to Write the Expression as a Single Function $$\theta$$

Multiple Choice

Use identities to write the expression as a single function of x or $$\theta$$
- $\sin ( x + 2 \pi )$

A) $- \cos x$
B) $\frac { \sqrt { 2 } } { 2 } \cos x - \frac { \sqrt { 2 } } { 2 } \sin x$
C) $\frac { \sqrt { 2 } } { 2 } \cos x + \frac { \sqrt { 2 } } { 2 } \sin x$
D) $\sin x$