# Need help finding the derivative of g(0)

• Oct 9th 2009, 09:23 AM
HighPoint
Need help finding the derivative of g(0)
The question is If g(x) + xsin(g(x))=x^2, and g(0)=pi find the derivative of g(0). I have no idea where to start. Thanks for any help.
• Oct 9th 2009, 10:11 AM
Jameson
Quote:

Originally Posted by HighPoint
The question is If g(x) + xsin(g(x))=x^2, and g(0)=pi find the derivative of g(0). I have no idea where to start. Thanks for any help.

Rewrite the equation as $g(x)=x^2-x\sin(g(x))$

Take the derivative on your own. This is the answer you can check

Spoiler:

$g'(x)=2x-(x\cos[g(x)]g'(x)+\sin(g(x)))$

Now plug in x=0 and use the fact that g(0)=pi.