[-П;-П/2]
[0;П/2]
[П;3П/2]
а³-8b³= a³-2³b³= a-(2b)³= (a-2b)×(a²+a×2b+(2b)²)= (a-2b)×(a²+2ab+4b²)
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Удачи вам!))
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