Question

( begin{aligned} I &=int e^{x} cos left(e^{x}right) d x & text { Let } sin left(e^{x}right)=t I & Rightarrow e^{x} cos left(e^{x}right) d x=d t I &=int d t=t+c &=sin left(e^{x}right)+c end{aligned} )

# THE THAT Exl. Evaluate le cos (e“)dx

Solution