Let $f ( x ) = \sin x \cos x$ Then $f ^ { \prime } ( x )$

Multiple Choice

Let $f ( x ) = \sin x \cos x$ Then $f ^ { \prime } ( x )$ is

A) $\sin ^ { 2 } x - \cos ^ { 2 } x$
B) $\cos ^ { 2 } x - \sin ^ { 2 } x$
C) 1
D) $2 \sin x \cos x$
E) $- 2 \sin x \cos x$