∵|a-2|+(b+1)²=0,∴a-2=0b+1=0∴a=2b=-15ab²-【2a²b-(4ab²-2a²b)】=5ab²-2a²b+4ab²-2a²b=9ab²-4a²b当a=2,b=-1时原式=18+16=34