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

问题描述:

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

=(x^2+X-2)+(2x^2+9x-5)-(3x^2-18x-3)
=28X+4