当(2b-1)²+3 丨a+2丨绝对值=0时,
2b-1=0,a+2=0
b=0.5,a=-2
2(a²b+ab²)-(2ab²-1+a²b)-2
=2(a²b+ab²)-(2ab²+a²b)-1
=a²b-1
=2-1
=1