可以检验该点在圆上, 直线OM的斜率是根号6/2, 所以切线的斜率是:-2/根号6=-根号6/3 切线过点(2,根号6), 解析式是: y-根号6=-根号6/3(x-2) y=-根号6x/3+5根号6/3
