(x+5)²-(x-2)(-3)2.(2x+2)(2x-3)-(x-1)(x+1)3.(a-b-3)(a+b+3)4.(2x-y)²-4(x-y)(x+2y)

问题描述:

(x+5)²-(x-2)(-3)
2.(2x+2)(2x-3)-(x-1)(x+1)3.(a-b-3)(a+b+3)4.(2x-y)²-4(x-y)(x+2y)

是让化简了吗

1.原式=x^2+10x+25+3x--6 =x^2+13x+19.2.原式=(4x^2--2x--6)--(x^2--1) =4x^2--2x--6--x^2+1 =3x^2--2x--5.3.原式=[a--(b+3)][a+(b+3)] =a^2--(b+3)^2 =a^...