Use Power Series to Solve the Differential Equation $y ^ { \prime } = 7 x ^ { 3 } y$

Multiple Choice

Use power series to solve the differential equation. $y ^ { \prime } = 7 x ^ { 3 } y$

A) $y ( x ) = 7 e ^ { \frac { x ^ { 4 } } { 4 } }$
B) $y ( x ) = c e ^ { 7 x }$
C) $y ( x ) = e ^ { - \frac { x ^ { 4 } } { 4 } }$
D) $y ( x ) = c e ^ { - \frac { 7 x ^ { 4 } } { 4 } }$
E) $y ( x ) = c e ^ { \frac { 7 x ^ { 4 } } { 4 } }$