计算①27a³b³-9a²b²-3ab²﹚÷﹙-3ab²﹚②[﹙a﹢b﹚³-2﹙a+b﹚²-3分之2﹙a+b﹚]÷3分之a+b.
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计算①27a³b³-9a²b²-3ab²﹚÷﹙-3ab²﹚②[﹙a﹢b﹚³-2﹙a+b﹚²-3分之2﹙a+b﹚]÷3分之a+b.
计算①27a³b³-9a²b²-3ab²﹚÷﹙-3ab²﹚②[﹙a﹢b﹚³-2﹙a+b﹚²-3分之2﹙a+b﹚]÷3分之a+b.
计算①27a³b³-9a²b²-3ab²﹚÷﹙-3ab²﹚②[﹙a﹢b﹚³-2﹙a+b﹚²-3分之2﹙a+b﹚]÷3分之a+b.
①27a³b³-9a²b²-3ab²﹚÷﹙-3ab²﹚
=3ab²(9a²b-3a-1)÷﹙-3ab²﹚
=-9a²b+3a+1
②[﹙a﹢b﹚³-2﹙a+b﹚²-3分之2﹙a+b﹚]÷3分之a+b.
=﹙a+b﹚ [﹙a+b﹚²-2﹙a+b﹚-2/3 ] *3/﹙a+b﹚
= [﹙a+b﹚²-2﹙a+b﹚-2/3 ] *3
=[ ﹙a+b-1﹚²-1-2/3]*3
=3﹙a+b-1﹚²-5