约分a²-ab+b²/a³+b³ x²-xy-2y²/x²-3xy+2y²
问题描述:
约分a²-ab+b²/a³+b³ x²-xy-2y²/x²-3xy+2y²
通分
3x/1-x²,-2x+1/x²-3x+2,1-x/2x-x²+3
尽量用初二的知识作答
答
a³+b³=(a²-ab+b²)*(a+b)
x²-xy-2y²=(x+y)*(x-2y)
x²-3xy+2y²=(x-y)*(x-2y)