已知:a3+b3=27,a2b-ab2=-6.求代数式(b3-a2)+(a2b-3ab2)-2(b3-a2b)的值.

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已知:a3+b3=27,a2b-ab2=-6.求代数式(b3-a2)+(a2b-3ab2)-2(b3-a2b)的值.
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已知:a3+b3=27,a2b-ab2=-6.求代数式(b3-a2)+(a2b-3ab2)-2(b3-a2b)的值.
已知:a3+b3=27,a2b-ab2=-6.求代数式(b3-a2)+(a2b-3ab2)-2(b3-a2b)的值.

已知:a3+b3=27,a2b-ab2=-6.求代数式(b3-a2)+(a2b-3ab2)-2(b3-a2b)的值.
题目打错了吧...应该是求(b3-a3)+(a2b-3ab2)-2(b3-a2b)吧?

-b3-a2-18

原式=b³-a³+a²b-3ab²-2b³+2a²b
=﹣﹙a³+b³﹚+3﹙a²b-ab²﹚
=﹣27-18
=﹣45

(b3-a3)+(a2b-3ab2)-2(b3-ab2)
=b3-a3+a2b-3ab2-2b3+2ab2 去括号
=(-b3-a3)+a2b-ab2 合并同类项
=-(a3-b3)+(a2b-ab2)
=-27-6 整体代换
=-33

原式=(b3-a3)+(a2b-3ab2)-2(b3-ab2)
=b3-a3+a2b-3ab2-2b3+2ab2
=(-b3-a3)+a2b-ab2
=-(a3-b3)+(a2b-ab2)
=-27-6 =-33