(3x^2-4)-(2x^2-x-5)-(4X-19)=?求此式

问题描述:

(3x^2-4)-(2x^2-x-5)-(4X-19)=?求此式

(3x^2-4)-(2x^2-x-5)-(4x-19)
=3x^2-4-2x^2+x+5-4x+19
=x^2-3x+20