(2x+1)(3x-2)-6x(x-1)-5x+9

问题描述:

(2x+1)(3x-2)-6x(x-1)-5x+9

(2x+1)(3x-2)-6x(x-1)-5x+9
=6x^2-x-2-6x^2+6x-5x+9
=7