=<u> x^2 </u> : <u>x+1</u> + <u> 2</u> = <u>(x-1)(x+2)(x-1)(x^2+x+1) </u> + 2x = 2x + (x-1)^2<u />
x^2+x+1 x^3-1 1/x (x^2+x+1)(x+1)