化简:3a²-【2ab²-2(-a²b-2(-a²b+4ab²)】-5ab²,其中a=-2,b=0.5,

化简:3a²-【2ab²-2(-a²b-2(-a²b+4ab²)】-5ab²,其中a=-2,b=0.5,
化简:3a²-【2ab²-2(-a²b-2(-a²b+4ab²)】-5ab²,其中a=-2,b=0.5,

化简:3a²-【2ab²-2(-a²b-2(-a²b+4ab²)】-5ab²,其中a=-2,b=0.5,
∵a=-2,b=0.5,∴ab=-1
3a²-【2ab²-2(-a²b-2(-a²b+4ab²)】-5ab²
=3×（-2）²-【-2b-2（a-2（a-4b）】+5b
=12-【-1-2（-2-2（-2-4×0.5】+5×0.5
=12-【-1-2（-2-2）】+2.5
=12-【-1+8】+2.5
=12-7+2.5
=7.5