已知a-b=1,a²+b²=13,求(a³-2b³)-(a²b-2ab²)-(ab²-b³)

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已知a-b=1,a²+b²=13,求(a³-2b³)-(a²b-2ab²)-(ab²-b³)

(a³-2b³)-(a²b-2ab²)-(ab²-b³)
=a³-2b³-a²b+2ab²-ab²+b³
=a³-b³-a²b+ab²
=(a-b)(a²+b²)
=1*13
=13

13