Find dydx\displaystyle \frac{{{\left.{d}{y}\right.}}}{{{\left.{d}{x}\right.}}} for y=cos(4x)2e4x\displaystyle {y}=\frac{{{\cos{{\left({4}{x}\right)}}}}}{{{2}{e}^{{{4}{x}}}}}.

dydx\displaystyle \frac{{{\left.{d}{y}\right.}}}{{{\left.{d}{x}\right.}}} =