Find F'(x)=x2(1 + cos(x))

Should I dist. the x^2?

I cannot seem to get started.

Thanks.

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- Feb 26th 2011, 04:04 PMFreaKariDunkTrig derv. problem
Find F'(x)=x2(1 + cos(x))

Should I dist. the x^2?

I cannot seem to get started.

Thanks. - Feb 26th 2011, 04:08 PMe^(i*pi)
Yes you can, then use the product rule on the second term: $\displaystyle F'(x) = x^2+x^2 \cos(x)$. Or you can use the product rule directly with $\displaystyle u = x^2 \text{ and } v = 1+\cos(x)$. You get the same result.

Out of interest are you trying to find the second derivative or is F'(x) a typo? - Feb 26th 2011, 04:10 PMFreaKariDunk
I have a whole gaggle of things I have to do with this problem, and I've been putting it off. But i want to get it done to go to a baseball game(fella watch) tomorrow. Sigh. Responsibility. Would Substitution be easier or should I just buck up and do it?

- Feb 26th 2011, 04:14 PMe^(i*pi)
A sub won't help, you'd still have to do the product rule which really isn't that much trouble

- Feb 26th 2011, 04:18 PMFreaKariDunk
so: 2x+2xCos(x)-x^2Sin(x)?

- Feb 26th 2011, 05:21 PMe^(i*pi)
- Feb 26th 2011, 05:34 PMNOX Andrew
Just in case FreaKariDunk reads this before e^(pi*i) gets back, factoring out x will actually give: $\displaystyle x \left ( 2 + 2\cos{x} - x\sin{x} \right )$.

- Feb 26th 2011, 05:41 PMFreaKariDunk
Thank you y'all for all your help. All work and No play makes me grumpy. :P