设,点P的坐标为(X,Y),点B坐标为(X1,Y1).
∵AP:PB=2:1=入,则有
X=(4+入*X1)/(1+入),Y=(0+入*Y1)/(1+入).
X1=(3X-4)/2,Y1=3Y/2.
把点(X1,Y1)代入X^2+Y^2=4中,得
[(3X-4)/2]^2+[3Y/2]^2=4.
(3X-4)^2+9Y^2=16.
点P的轨迹方程是:(3X-4)^2+9Y^2=16.
设,点P的坐标为(X,Y),点B坐标为(X1,Y1).
∵AP:PB=2:1=入,则有
X=(4+入*X1)/(1+入),Y=(0+入*Y1)/(1+入).
X1=(3X-4)/2,Y1=3Y/2.
把点(X1,Y1)代入X^2+Y^2=4中,得
[(3X-4)/2]^2+[3Y/2]^2=4.
(3X-4)^2+9Y^2=16.
点P的轨迹方程是:(3X-4)^2+9Y^2=16.