1.8m^2-9[4mn+m^2-3(2m^2+mn)]+(-10m^2-2mn)=?2.1/4a^2b^2[3ab(a+b)-5a(ab-b^2)]

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1.8m^2-9[4mn+m^2-3(2m^2+mn)]+(-10m^2-2mn)=?2.1/4a^2b^2[3ab(a+b)-5a(ab-b^2)]
1.8m^2-9[4mn+m^2-3(2m^2+mn)]+(-10m^2-2mn)=?2.1/4a^2b^2[3ab(a+b)-5a(ab-b^2)]

1.8m^2-9[4mn+m^2-3(2m^2+mn)]+(-10m^2-2mn)=?2.1/4a^2b^2[3ab(a+b)-5a(ab-b^2)]
1. 8m^2-9[4mn+m^2-3(2m^2+mn)]+(-10m^2-2mn)
=8m²-36mn-9m²+54m²+27mn-10m²-2mn
=43m²-11mn
2. 1/4a^2b^2[3ab(a+b)-5a(ab-b^2)]
=a²b²/4(3a²b+3ab²-5a²b+5ab²)
=-a^4b³/2+2a³b^4

1、原式=8m²-9(mn+5m²)-10m²-2mn
=(8+45-10)m²-(9+2)mn
=43m²-11mn
2、原式=1/4a²b²(3a²b+3ab²-5a²b+5ab²)
=1/4a²b² (8ab²-2a²b)
=(b-a)/2ab