解析:a=b²......①b=2a.....②//①隐含a≥0,于是②中b≥0②代入①得,a=(2a)²即,a(4a-1)=0解得,a=0或1/4a=0时,b=0a=1/4时,b=2a=1/2综上,(a,b)=(0,0)或(1/4,1/2)