若（2a-b)零次方=1,则分式a²-3ab+2b²分之a²+2ab-b²

若（2a-b)零次方=1,则分式a²-3ab+2b²分之a²+2ab-b²
若（2a-b)零次方=1,则分式a²-3ab+2b²分之a²+2ab-b²

若（2a-b)零次方=1,则分式a²-3ab+2b²分之a²+2ab-b²
（2a-b)零次方≠1 (本题改一下,否则不好做)
所以
2a=b
a²-3ab+2b²分之a²+2ab-b²
=(a²+2ab-b²)/(a²-3ab+2b²)
=(a²+4a²-4a²)/(a²-6a²+8a²)
=a²/3a²
=1/3