设B(a,b),P(x,y)
因为BP∶PA=1∶2
即2BP=PA
即2(x-a)=3-x
2(y -b)=1-y
整理:x=(3+2a)/3,则a=(3x-3)/2
y=(1+2b)/3,则b=(3y-1)/2
又B在圆x^2+y^2=4上,
(3x-3)^2+(3y-1)^2=16
设B(a,b),P(x,y)
因为BP∶PA=1∶2
即2BP=PA
即2(x-a)=3-x
2(y -b)=1-y
整理:x=(3+2a)/3,则a=(3x-3)/2
y=(1+2b)/3,则b=(3y-1)/2
又B在圆x^2+y^2=4上,
(3x-3)^2+(3y-1)^2=16