Помогите срочно!!!!!!! номер 680.
1.х³+ху+х²у²+у³ 2)m^4-m²n+2m²n²-2n³ 3)12a^4-a²b²-b^4 4)5x³-4x²+5x²-4x=5x³+x²-4x 5)4a^4-3a³-8a³+6a²=4a^4-11a³+6a² 6)56p³-16p²-35p²+10p=56p³-51p²+10p
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