解
[(a+b)^5-(a+b)^3]÷(a+b)^3
=(a+b)²-1
=(a+b-1)(a+b+1)
[(x+2y)(x-2y)+4(x-y)²]÷6x
=[x²-4y²+4x²-8xy+4y²]÷6x
=[5x²-8xy]÷6x
=(5x-8y)/6
(x²-6x+9)÷(x-3)
=(x-3)²÷(x-3)
=x-3第1题答案是a²﹢2ab﹢b²﹣1怎么来的 过程[(a+b)^5-(a+b)^3]×1/(a+b)^3=[(a+b)^5×1/(a+b)^3]-[(a+b)^3×1/(a+b)^3]=(a+b)²-1=a²+2ba+b²-1