Use the Given Information to Find the Exact Value of the Trigonometric

Multiple Choice

Use the given information to find the exact value of the trigonometric function.
- $\sin \theta = - \frac { 15 } { 17 } , \theta$ lies in quadrant IV Find $\cos \frac { \theta } { 2 }$ .

A) $- \frac { 5 \sqrt { 34 } } { 34 }$
B) $\frac { 5 \sqrt { 34 } } { 34 }$
C) $\frac { 4 } { 17 }$
D) $- \frac { 3 \sqrt { 34 } } { 34 }$