# Derivitive

• Oct 11th 2008, 05:19 PM
skyslimit
Derivitive
The derivitive of $200(80-x^2)$ is not $-400x(80-x^2)$ ?

what else could it be ?
• Oct 11th 2008, 05:23 PM
NidhiS
No(Shake)
it's -400 x
• Oct 11th 2008, 05:33 PM
skyslimit
Mhm... I see. Confusing with the chain rule.
• Oct 11th 2008, 05:39 PM
NidhiS
well u don't need to use the chain rule here.I mean chain rule would have worked if there was soemthing like this
200x(1+800x) u see the difference.In this case the easiest thing to do would be to multiple both the terms with 200 and then differentiate it but then

you cna use teh chain rule as well and it will work because there are 2 x's .idk

hope that helps(Worried)