拟圆周的两个几何性质

O1; In this paper,the following two results are obtained:(1) IfГ is a Jordan curve of R2,∞∈Г,thenГ is a quasicirc1e if and only if there exists a constant k,1≤k＜+∞,such that for any four points z 1 ,z2 ,w1 ,w2 ∈Г,there exists a k-quasiconformal mapping h of R2 with h (∞)=∞,h(ГГ)=ГГ and h(zj)=wj(j=1,2).(2)If Г is a Jordan curve of R2,then Г is a quasicircle if and only if Г is a bounded circular distortion curve.