`y=sin(e^(3x))`

Let `y=sin u`, where `u=e^(3x)`

`(dy)/(dx)=(dy)/(du)(du)/(dx)`

`=[cos u](d(e^(3x)))/(dx)`

`=[cos e^(3x)](3e^(3x))`

`=3e^(3x)\ cos e^(3x)`

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