题目内容
若半径为1的动圆与圆(x-1)2+(y+2)2=16相切,则动圆圆心的轨迹方程是
(x-1)2+(y+2)2=5或(x-1)2+(y+2)2=3
(x-1)2+(y+2)2=25
(x-1)2+(y+2)2=9
(x-1)2+(y+2)2=25或(x-1)2+(y+2)2=9