1.a(2x+y)(x-y)-a(x-y)^2
=a(x-y)[(2x+y)-(x-y)]
=a(x-y)(x+2y)
2.(a^2+b^2)-4a^2b^2
=(a²+b²+2ab)(a²+b²-2ab)
=(a+b)²(a-b)²
3.y^3+5y^2-24y
=y(y²+5y-24)
=y(y+8)(y-3)4（x-1）^2-(1-x)^24（x-1）^2-(1-x)^2=4(x-1)²-(x-1)²=3(x-1)²