完全平方和绝对值非负
所以2a+b+3=0
b-1=0
b=1
a=-2
5a+{-2b-3[2b-8+(3a-2b-1)-a]+1}
=5a+{-2b-3[2b-8+3a-2b-1-a]+1}
=5a+{-2b-3[2a-9]+1}
=5a+{-2b-6a+27+1}
=5a-6a-2b+28
=-a-2b+28
=2-2+28
=28