Solve the Initial-Value Problem $$\frac { d u } { d t } = \frac { 2 t + \sec ^ { 2 } t } { 2 u } , u ( 0 ) = 4$$

Solve the initial-value problem.
$$\frac { d u } { d t } = \frac { 2 t + \sec ^ { 2 } t } { 2 u } , u ( 0 ) = 4$$