(5m³n-8mn²-2n⁶)×(-4m²n⁸)=
=5m³n(-4m²n^8) – 8mn²(-4m²n^8) – 2n^6(-4m²n^8)=
=-20m^5n^9 + 32m³n^10 +8m²n^14
вроде так
(5m³n-8mn²-2n⁶)×(-4m²n⁸)=
=5m³n(-4m²n^8) – 8mn²(-4m²n^8) – 2n^6(-4m²n^8)=
=-20m^5n^9 + 32m³n^10 +8m²n^14
вроде так