1. 2 cosh^2 3x

what is this differentiated

2 cosh^2 3x

thanks

2. Originally Posted by thrusterkel
what is this differentiated

2 cosh^2 3x

thanks
note that $\frac d{dx} \cosh u = u' \sinh u$ where $u$ is a function of $x$

use that fact along with the Chain rule and you'll have the answer

try it and tell me what you get