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.
- $\sin \theta = \frac { 1 } { 4 } , \tan \theta > 0 \quad$ Find $\cos \frac { \theta } { 2 }$ .

A) $\frac { \sqrt { 8 + 2 \sqrt { 15 } } } { 4 }$
B) $\frac { \sqrt { 10 } } { 4 }$
C) $\frac { \sqrt { 6 } } { 4 }$
D) $\frac { \sqrt { 8 - 2 \sqrt { 15 } } } { 4 }$