合并同类项:3x^2-[7x-2(4x+2)+2x^2]-x^2
问题描述:
合并同类项:3x^2-[7x-2(4x+2)+2x^2]-x^2
答
3x^2-[7x-2(4x+2)+2x^2]-x^2
=3x^2-[7x-8x-4+2x^2]-x^2
=3x^2+x+4-2x^2-x^2
=x+4