2х^2+7х+9/х^3-1 + 4х+3/х^2+х+1 - 5/х-1, при х=1,1

(2x²+7x+9)/(x-1)(x²+x+1) +(4x+3)/(x²+x+1)=(2x²+7x+9+4x²-4x+3x-3)/(x³-1)=
=(6x²+6x+6)/(x³-1)=6(x²+x+1)/(x-1)(x²+x+1)=6/(x-1)
x=1,1      6/(1,1-1)=6/0,1=60