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Topic: How do I do this???
Replies: 3   Last Post: Jan 24, 2005 2:19 AM

 Messages: [ Previous | Next ]
 George Cox Posts: 868 Registered: 12/6/04
Re: How do I do this???
Posted: Jan 24, 2005 2:19 AM

Stephanie wrote:
>
> How the heck do I multiply these together??
>
> (x - .5) (x - 7.8) (x - 8.7) ??? PLEASE HELP!

In two stages so that nothing gets lost:

(x - .5)*(x - 7.8) = x^2 - 7.8*x -.5*x + 3.9

= x^2 - 8.3*x + 3.9

And then:

(x^2 - 8.3*x + 3.9)*(x - 8.7)

= x^3 - 8.7*x^2 - 8.3*x^2 + 72.21*x + 3.9*x - 33.93

= x^3 - 17*x^2 + 76.11*x - 33.93

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Date Subject Author
1/24/05 Chergarj
1/24/05 ticbol
1/24/05 George Cox