已知圆(x+2)²+y²=25/4的圆心为m,圆(x-2)²+y²=1/4的圆心为n,一动圆与这两个圆都相切,求动圆圆心的轨迹方程
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![已知圆(x+2)²+y²=25/4的圆心为m,圆(x-2)²+y²=1/4的圆心为n,一动圆与这两个圆都相切,求动圆圆心的轨迹方程](/uploads/image/z/13333736-56-6.jpg?t=%E5%B7%B2%E7%9F%A5%E5%9C%86%EF%BC%88x%EF%BC%8B2%EF%BC%89%26%23178%3B%EF%BC%8By%26%23178%3B%EF%BC%9D25%2F4%E7%9A%84%E5%9C%86%E5%BF%83%E4%B8%BAm%2C%E5%9C%86%EF%BC%88x%EF%BC%8D2%EF%BC%89%26%23178%3B%EF%BC%8By%26%23178%3B%EF%BC%9D1%2F4%E7%9A%84%E5%9C%86%E5%BF%83%E4%B8%BAn%2C%E4%B8%80%E5%8A%A8%E5%9C%86%E4%B8%8E%E8%BF%99%E4%B8%A4%E4%B8%AA%E5%9C%86%E9%83%BD%E7%9B%B8%E5%88%87%2C%E6%B1%82%E5%8A%A8%E5%9C%86%E5%9C%86%E5%BF%83%E7%9A%84%E8%BD%A8%E8%BF%B9%E6%96%B9%E7%A8%8B)
已知圆(x+2)²+y²=25/4的圆心为m,圆(x-2)²+y²=1/4的圆心为n,一动圆与这两个圆都相切,求动圆圆心的轨迹方程
已知圆(x+2)²+y²=25/4的圆心为m,圆(x-2)²+y²=1/4的圆心为n,一动圆与这两个圆都相切,求动圆圆心的轨迹方程
已知圆(x+2)²+y²=25/4的圆心为m,圆(x-2)²+y²=1/4的圆心为n,一动圆与这两个圆都相切,求动圆圆心的轨迹方程
设轨迹圆方程(x-a)²+(y-b)²=r²,
动圆圆心到m点距离等式:(r+2.5)²=(a+2)²+b²(半径和平方=圆心距平方)
动圆圆心到n点距离等式:(r+0.5)²=(a-2)²+b²
解得:a=r+1.5;b²=2r;(r>=0.5)
b²=2(a-1.5);
结果:y²=2x-3(x>=2);
自己开根号,不好打