过圆心做AC的垂线,垂足为H,设垂线长为h,DH长为x,大圆和小圆半径分别为R和r.
则有:
R^2-h^2=(3/2+x)^2
R^2-r^2=3
r^2-h^2=x^2
将后两式相加联立一式得:3+x^2=(3/2+x)^2,解得x=1/4
故AC=3+2x=7/2
过圆心做AC的垂线,垂足为H,设垂线长为h,DH长为x,大圆和小圆半径分别为R和r.
则有:
R^2-h^2=(3/2+x)^2
R^2-r^2=3
r^2-h^2=x^2
将后两式相加联立一式得:3+x^2=(3/2+x)^2,解得x=1/4
故AC=3+2x=7/2