If y=(5x)sin(4x)\displaystyle {y}={\left({5}{x}\right)}^{{{\sin{{\left({4}{x}\right)}}}}}, then

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

(Be sure to express your answer in terms of x\displaystyle {x})