Just quick:
I have (2x^4)+(4x^3)-(5x^2)-5x+2.
The only possible rational roots by the Rational Root Test are 1,-1,2,-2,.5,-.5.
The only one that works out of these is -1. Could someone just check this for me?
Jimmy
I agree. Good work!
You can always check these by division as well. You should be able to divide $\displaystyle 2x^4+4x^3-5x^2-5x+2$ by x - (-1) either by long or synthetic division to find:
$\displaystyle 2x^4+4x^3-5x^2-5x+2 = (x+1)(2x^3+2x^2-7x+2)$
confirming that there is no remainder.
-Dan