Maths questions??(9)

By sine law,
a/sin A = b/sin B = c/sin C = 2R
(a,b,c是三角形的邊 ; A,B,C是三角形的角 ; A,B,C的對邊分別是a,b,c ; R是circumcircle的radius)
∴when R is constant,
length of the line is direct proportion with sin of the angle

2007-01-28 13:00:38 補充：
最後那行有些修正:length of the line is direct proportion with Sine of the angle