苏教版数学《必修2》教材中有一道探究题目:已知圆C:x2+y~2=r~2,直线l:ax+by=r~2.(1)当点P(a,b)在圆C上时,直线l与圆C具有怎样的位置关系?(2)当点P(a,b)在圆C外时,直线l具有什么特点?问题的解决依靠圆心到直线的距离与圆半径的 Sujiao version of mathematics “compulsory 2” textbook has a research topic: Known circle C: x2 + y ~ 2 = r ~ 2, the line l: ax + by = r ~ 2. (1) b) What is the relationship between the line l and the circle C when it is on the circle C? (2) What is the characteristic of the line l when the point P (a, b) is outside the circle C? The solution to the problem relies on the center-to- Distance with the radius of the circle