Solve the separable differential equation for u\displaystyle {u}

dudt=e3u+3t.\displaystyle \frac{{{d}{u}}}{{{\left.{d}{t}\right.}}}={e}^{{{3}{u}+{3}{t}}}.

Use the following initial condition: u(0)=5\displaystyle {u}{\left({0}\right)}={5}.

u=\displaystyle {u}=