# Derivative of Sine

• May 15th 2010, 08:40 AM
p4pri
Derivative of Sine
Hey,

how would you differentiate y=xsinx

I got xcosx
but that's wrong.
• May 15th 2010, 08:44 AM
Quote:

Originally Posted by p4pri
Hey,

how would you differentiate y=xsinx

I got xcosx
but that's wrong.

Hi p4pri,

$xsinx$ is a product, hence you need to use the product rule of differentiation.

$\frac{d}{dx}xsinx=x\frac{d}{dx}sinx+sinx\frac{d}{d x}x$