Evaluate the Integral $$\int 15 x \cos \frac { 1 } { 2 } x d x$$

Multiple Choice

Evaluate the integral.
- $$\int 15 x \cos \frac { 1 } { 2 } x d x$$

A) $30 x \sin \left( \frac { 1 } { 2 } \right) x + 60 \cos \left( \frac { 1 } { 2 } \right) x + C$
B) $60 \sin \left( \frac { 1 } { 2 } \right) x - 30 x \cos \left( \frac { 1 } { 2 } \right) x + C$
C) $15 x \sin \left( \frac { 1 } { 2 } \right) x - 30 \cos \left( \frac { 1 } { 2 } \right) x + C$
D) $15 \sin \left( \frac { 1 } { 2 } \right) x + 30 x \cos \left( \frac { 1 } { 2 } \right) x + C$