由题意得分子=0且分母≠0,
∴|a-2|+(b-3)²=0且a+b≠0,
∴a-2=0,b-3=0,
a=2,b=3,a+b=5≠0,符合题意,
把a=2,b=3代入得,
(a²-ab)/b²-(a²-ab)/(a²-b²)
=(a²-ab)/b²-a/(a+b)
=(2²-2*3)/3²-2/(2+3)
=-2/9-2/5
=-28/45
由题意得分子=0且分母≠0,
∴|a-2|+(b-3)²=0且a+b≠0,
∴a-2=0,b-3=0,
a=2,b=3,a+b=5≠0,符合题意,
把a=2,b=3代入得,
(a²-ab)/b²-(a²-ab)/(a²-b²)
=(a²-ab)/b²-a/(a+b)
=(2²-2*3)/3²-2/(2+3)
=-2/9-2/5
=-28/45