# HELP!! Find f(x) for the given function...

• Sep 15th 2008, 04:09 PM
tiar
HELP!! Find f(x) for the given function...
Find f(x) for the given function f and simplify as much as possible
$
f(x)=x^3-2x^2+20$

I'm really, really rusty...just started precalculus this fall and I can't remember how to do this (with the $x^3$...what is it called again?)
• Sep 15th 2008, 04:12 PM
icemanfan
You already have $f(x)$, so you must be looking for something else. If it's the derivative of f(x), remember the power rule: $\frac{d}{dx} x^n = nx^{n-1}$. And the derivative of a sum of terms is the sum of the derivatives of each of the individual terms.
• Sep 15th 2008, 04:15 PM
tiar
Quote:

Originally Posted by icemanfan
You already have $f(x)$, so you must be looking for something else. If it's the derivative of f(x), remember the power rule: $\frac{d}{dx} x^n = nx^{n-1}$. And the derivative of a sum of terms is the sum of the derivatives of each of the individual terms.

OH! I misinterpreted the question. Thank you, this is much easier than I thought it was, haha.