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I'm a bit lost and how I would go about creating a general formula for differentiating this equation. Find $f^{(n)}(x)$ for $$f(x) = 5x^4-8x^3+6x^2-1.$$

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Is it $f(x)\cdots f(x)$ or $(f\circ\ldots\circ f)(x)$ or $f^{(n)}(x)$? I guess that's the latter now that I see you mention differentiation. Denoting the $n$-th derivative $f^n$ is very confusing and uncommon, I think. –  1015 Apr 10 '13 at 3:26
You can use the general formula in this problem. –  Mhenni Benghorbal Apr 10 '13 at 3:29

1 Answer 1

Just take a few derivatives and see the pattern. I guarantee you will be happy after the fifth/sixth derivative.

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I can see the pattern that is forming, but I'm having trouble with how I should write down the general formula. –  adeshina lawel Apr 10 '13 at 4:10
What I've gotten so far: –  adeshina lawel Apr 10 '13 at 4:11
5(4-n)!x^(4-n) ect... something like that? –  adeshina lawel Apr 10 '13 at 4:12
Did you get to the sixth derivative? –  Fixed Point Apr 10 '13 at 4:13

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