化简求值b/(a-b)-b³/(a³-2a²b+ab²)÷(ab+b²)/(a²-b²),其中a=-2,b=3亲们啊

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化简求值b/(a-b)-b³/(a³-2a²b+ab²)÷(ab+b²)/(a²-b²),其中a=-2,b=3亲们啊
化简求值b/(a-b)-b³/(a³-2a²b+ab²)÷(ab+b²)/(a²-b²),其中a=-2,b=3
亲们啊

化简求值b/(a-b)-b³/(a³-2a²b+ab²)÷(ab+b²)/(a²-b²),其中a=-2,b=3亲们啊
原式=b/(a-b)-b³/a(a-b)²÷[b(a+b)/(a+b)(a-b)]}
=b/(a-b)-b³/a(a-b)²×[(a-b)/b]
=b/(a-b)-b²/a(a-b)
=(ab-b²)/a(a-b)
=b/a
当a=-2,b=3时
原式=b/a=3/(-2)=-3/2