Question

已知 圆O1、圆O2的半径分别为R和r(R>r),圆心距为d x^2-2(d-R)x+r^2=0

Answer 1

x^2-2(d-R)x+r^2=0

化为[x-(d-R)]^2-(d-R)^2+r^2=0--------------(1)

(d-R)^2-r^2=（d-R+r）*（d-R-r）----------(2)

式（d-R+r）〉0

式（d-R-r）< 0

(2)结果