# Math Help - sinh

1. ## sinh

hi there,

can anyone help me with the derivative of sinh(3x)

2. Originally Posted by kate45
hi there,

can anyone help me with the derivative of sinh(3x)

$\sinh(3x)=\frac{e^{3x}-e^{-3x}}{2}$

$\cosh(3x)=\frac{e^{3x}+e^{-3x}}{2}$

$\frac{d}{dx}\sinh(3x)=\frac{d}{dx}\left( \frac{e^{3x}-e^{-3x}}{2}\right)=3\left( \frac{e^{3x}+e^{-3x}}{2}\right)=3\cosh(3x)$

3. or simply, if you already know the derivative of sinh x, just apply chain rule..