5ab²-{2a²b-3[ab²-2(2ab²+a²b)]
=5ab²-{2a²b-3[ab²-4ab²-2a²b)]
=5ab²-{2a²b-3[-3ab²-2a²b]
=5ab²-{2a²b+9ab²+6a²b]
=5ab²-{8a²b+9ab²]
=5ab²-8a²b-9ab²
=-8a²b-4ab²
∵│a+1│+(b-2)²=0
∴a=-1,b=2
则原式=-16+16=0
5ab²-{2a²b-3[ab²-2(2ab²+a²b)]
=5ab²-{2a²b-3[ab²-4ab²-2a²b)]
=5ab²-{2a²b-3[-3ab²-2a²b]
=5ab²-{2a²b+9ab²+6a²b]
=5ab²-{8a²b+9ab²]
=5ab²-8a²b-9ab²
=-8a²b-4ab²
∵│a+1│+(b-2)²=0
∴a=-1,b=2
则原式=-16+16=0