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notamathwiz
Aug 2, 2008, 12:57 PM
Its me once again...

This is another question I am stumped on.

find f(-4) for f(x)=x^3-x^2+x+1

(use remainder theorem) I have no clue what remainder theorem is

what I have so far is f(x)=-4^3+4^2+-4+1

I tried to solve it by solving the exponent values

so f(x)= -64+16-4+1

then f(x)= -48+-4+1

and f(x)= -52+1

f(x)= -51

I am not even sure if I solved that portion correctly. And of course I have no clue what the remainder theorem is... PLEASE HELP!!

DrLang
Aug 2, 2008, 01:05 PM
You have the idea right, but I'm not sure where that third (-4) came from in your substitution.

notamathwiz
Aug 2, 2008, 01:13 PM
Its me once again ...

This is another question I am stumped on.

find f(-4) for f(x)=x^3-x^2+1

(use remainder theorem) I have no clue what remainder theorem is

what I have so far is f(x)=-4^3+4^2+-4+1

I tried to solve it by solving the exponent values

so f(x)= -64+16-4+1

then f(x)= -48+-4+1

and f(x)= -52+1

f(x)= -51

I am not even sure if i solved that portion correctly. And of course I have no clue what the remainder theorem is ... PLEASE HELP!!!
I actually copied the question down wrong... it is find f(-4) for f(x)=x^3-x^2+x+1 I forgot the extra x after the x^2 and before the 1 I CORRECTED THE PROBLEM

DrLang
Aug 2, 2008, 01:25 PM
I actually copied the question down wrong ... it is find f(-4) for f(x)=x^3-x^2+x+1 I forgot the extra x after the x^2 and before the 1 I CORRECTED THE PROBLEM
Here's a guide on what the remainder theorem is and how to use it. It is a method for solving quadratic equations.
The Remainder Theorem (http://www.purplemath.com/modules/remaindr.htm)

Unknown008
Aug 3, 2008, 09:00 PM
Everywhere, since you substituted the 'x' by '-4', you should put f(-4), OK?