Use Logarithmic Differentiation to Find $f ^ { \prime } ( x )$

Multiple Choice

Use logarithmic differentiation to find $f ^ { \prime } ( x )$ . $f ( x ) = \sqrt [ 8 ] { \frac { 6 x + 5 } { 8 + 6 x } }$

A) $f ^ { \prime } ( x ) = \frac { 1 } { 8 } \left( \frac { 6 } { 6 x + 5 } - \frac { 6 } { 8 + 6 x } \right) f ( x )$
B) $f ^ { \prime } ( x ) = f ( x ) \left( \frac { 6 x + 5 } { 8 + 6 x } \right) ^ { - 7 / 8 }$
C) $f ^ { \prime } ( x ) = \left( \frac { 6 } { 6 x + 5 } - \frac { 6 } { 8 + 6 x } \right) f ( x )$
D) $f ^ { \prime } ( x ) = \left( \frac { 6 x + 5 } { 8 + 6 x } \right) ^ { - 7 / 8 }$