(1)[4a(2a-3ab²)-3a²b4-5b)]÷(-½ab) 需要清晰的过程,

问题描述:

(1)[4a(2a-3ab²)-3a²b4-5b)]÷(-½ab) 需要清晰的过程,
(2)分解因式:a(x-y)-2(y-x)²-(x+y)(x-y)需要清晰的过程,
(3)(x-3+2y)-2(y-x)²-2(2x-y)(x+2y)需要清晰的过程,
(4)(9-a²)²-(3-a)(a+3)(a²+9)需要清晰的过程,
(5)已知(a-b)²=4,求ab的值和(a+b)²的值需要清晰的过程,

2,原式=(x-y)[a-2(x-y)-(x+y)]=(x-y)(a-2x+2y-x-y)=(x-y)(a-3x+y)