# Calculators Ti 89 and polynomials

1. Nov 6, 2007

### Motox7

okay, so i know how to factor( and the expand(

but i have a question for dividing polynomials such as...

9x^5-6x^3+x-63 / x-8

how do i enter this into my calculatoor?! AHH its driving me INSANEEEEEEEEEe

i get 9x^5-6x^3+x-63/x-8 but my teacher gets a different everytime for every problem similar to this...ahhh.

what do i dooooooo

2. Nov 6, 2007

### d_leet

Enter it into your calculator as (9x^5-6x^3+x-63)/(x-8), but you could always just do the division yourself instead of on your calculator.

3. Nov 6, 2007

4. Nov 6, 2007

### SnipedYou

Personally I think it is easier and quicker to synthetically divide then to waste my time plugging it into a calculator.

If you don't know what synthetic division is, you can read about it at the bottom of this page.

http://www.purplemath.com/modules/remaindr.htm

5. Nov 7, 2007

### robert Ihnot

ranger: Use propFrac() located in the algebra menu.

The TI-89 is often difficult (awkward) to use. The problem here is that 8 is not a root of the polynomial. Ranger hit the nail on the head. As for the Algebra menu, it's sort of hidden under the Math menu being the ninth function.

6. Dec 2, 2007

### rs1n

The problem is with the order of operations:

9x^5-6x^3+x-63 / x-8

gets treated as:

9x^5-6x^3+x- (63/x) -8

Presumably you meant (9x^5-6x^3+x-63)/(x-8); as d_leet suggested, enter it exactly in this form.

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