已知x^2-4x+2=0,则(x-1)^2-2(x+1)的值为______

问题描述:

已知x^2-4x+2=0,则(x-1)^2-2(x+1)的值为______

(x-1)^2-2(x+1)
=x²-2x+1-2x-2
=x²-4x+2-3
=-3