# look for the value that satisfies the equation

• Mar 28th 2013, 11:27 PM
Renrie
look for the value that satisfies the equation
please explain how can I answer this one :) I know the answer should be a.) -4 & b.) -1.
could you explain how will I come up with that answer? Thank you :)

Attachment 27728
• Mar 29th 2013, 05:59 AM
Ruun
Re: look for the value that satisfies the equation
Hint $x^3+x^2+ax+1=(x-x_1)(x^2+2x-2)$ or $\frac{x^3+x^2+ax+1}{x^2+2x-2}=(x-x_1)$
• Mar 29th 2013, 07:27 AM
HallsofIvy
Re: look for the value that satisfies the equation
That's very clever! I would have just solved $x^2+ 2x- 2$ to see that the only x that satisfy that equation are $-1+\sqrt{3}$ and $-1- \sqrt{3}$, then put those into P to see how I could cancel that irrational " $\sqrt{3}$" part. But Ruun's hint is much simpler.
• Mar 30th 2013, 03:00 AM
pauliana
Re: look for the value that satisfies the equation
I'm trying to solve it to but I don't get the equation. should I substitute the given?
• Mar 30th 2013, 06:07 AM
HallsofIvy
Re: look for the value that satisfies the equation
You have been told two different ways to solve this problem. Please show what you have tried and where you are stuck.