已知实数xy满足x2+y2-4x+3=0则(x+y-3)/(x-y+1)的取值范围是

已知实数xy满足x2+y2-4x+3=0则(x+y-3)/(x-y+1)的取值范围是
已知实数xy满足x2+y2-4x+3=0则(x+y-3)/(x-y+1)的取值范围是

已知实数xy满足x2+y2-4x+3=0则(x+y-3)/(x-y+1)的取值范围是

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