当a=-2,b=-3时,求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值当a=-2,b=-3时,求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值

当a=-2,b=-3时,求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值当a=-2,b=-3时,求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值
当a=-2,b=-3时,求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值
当a=-2,b=-3时,
求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值

当a=-2,b=-3时,求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值当a=-2,b=-3时,求3a²b-[2a²b-(2ab-a²b)-4a²]-3ab的值
3a²b-[2a²b-(2ab-a²b)-4a²]-3ab
=3a²b-[2a²b-2ab+a²b-4a²]-3ab
=3a²b-[3a²b-2ab-4a²]-3ab
=2ab+4a²-3ab
=-ab+4a²
=-（-2*-3）+4*（-2）²
=-6+16
=10

3a²b-[2a²b-(2ab-a²b)-4a²]-3ab

原式=3a²b-[2a²b-2ab+a²b-4a²]-3ab
=3a²b-[3a²b-2ab-4a²]-3ab
=3a²b-3a²b+2ab+4a&...

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3a²b-[2a²b-(2ab-a²b)-4a²]-3ab

原式=3a²b-[2a²b-2ab+a²b-4a²]-3ab
=3a²b-[3a²b-2ab-4a²]-3ab
=3a²b-3a²b+2ab+4a²-3ab
=4a²-ab
当a=-2, b=-3时，
原式=4×4-6=10

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3a²b-[2a²b-(2ab-a²b)-4a²]-3ab=4a²-ab
4*(-2)²-(-2)*(-3)=16-6=10

当a=-2, b=-3时，3a²b-[2a²b-(2ab-a²b)-4a²]-3ab
=3a²b-2a²b+(2ab-a²b)+4a²-3ab
=a²b+2ab-a²b+4a²-3ab
=4a²-ab
=4a(a-b)
=4×(-2)×(-2+3)
=-8