Given f(x) = (x^3-2x)/sqrt(2x+1) find f'(x)

I can do the first step but then I'm stuck.. Can't wait to fail my test friday.

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- Mar 3rd 2010, 09:07 PMtbenne3derivative problem
Given f(x) = (x^3-2x)/sqrt(2x+1) find f'(x)

I can do the first step but then I'm stuck.. Can't wait to fail my test friday.

- Mar 3rd 2010, 09:09 PMDrexel28
- Mar 3rd 2010, 09:33 PMtbenne3
- Mar 3rd 2010, 09:34 PMexperiment00005
Just use the quotient rule, taking the chain rule into consideration. Are you still stuck after that? I'm not sure what 'step' you're on in your solution. ^^

- Mar 3rd 2010, 09:41 PMtbenne3
- Mar 4th 2010, 04:03 AMHallsofIvy
The square root: $\displaystyle \sqrt{f(x)}= (f(x))^{1/2}$ so, by the chain rule, its derivative is $\displaystyle (1/2)(f(x))^{-1/2}f'(x)$.

- Mar 9th 2010, 04:47 AMmr fantastic
Asked again here: http://www.mathhelpforum.com/math-he...erivative.html

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