Express the Sum or Difference as a Product of Sines $$\cos \frac { 5 \theta } { 2 } + \cos \frac { 3 \theta } { 2 }$$

Multiple Choice

Express the sum or difference as a product of sines and/or cosines.
- $$\cos \frac { 5 \theta } { 2 } + \cos \frac { 3 \theta } { 2 }$$

A) $2 \sin ( 2 \theta ) \sin \theta$
B) $2 \cos ( 2 \theta ) \cos \frac { \theta } { 2 }$
C) $2 \sin ( 2 \theta ) \sin \frac { \theta } { 2 }$
D) $2 \cos ( 2 \theta )$