Question

MATLAB程序求切点,已知一圆和圆外一点，求过点的圆的切点

Answer 1

代码：

x0=1;y0=2;%圆心坐标

r0=3;%圆半径

x1=5;y1=2+3;%点的坐标

k1=(y0*x0+y1*x1-y0*x1-y1*x0+(r0^2*(-2*y0*y1-2*x0*x1+y1^2+y0^2+x0^2-r0^2+x1^2))^(1/2))/(-r0^2+x0^2-2*x0*x1+x1^2)

k2= (y0*x0+y1*x1-y0*x1-y1*x0-(r0^2*(-2*y0*y1-2*x0*x1+y1^2+y0^2+x0^2-r0^2+x1^2))^(1/2))/(-r0^2+x0^2-2*x0*x1+x1^2)

x_1=(-k1*y1+x0+k1^2*x1+y0*k1)/(1+k1^2)

y_1 =-(-y1-k1*x0-y0*k1^2+k1*x1)/(1+k1^2)

x_2=(-k2*y1+x0+k2^2*x1+y0*k2)/(1+k2^2)

y_2 =-(-y1-k2*x0-y0*k2^2+k2*x1)/(1+k2^2)

追问

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http://zhidao.baidu.com/question/684740974756360692.html