Uhol

S = Intersect(xAxis, yAxis)
L = (4, 3)
c = Circle(S, L)
B = Point(c)
B_1 = Rotate(B, 120°, S)
g = Segment(S, B)
C = Point(c)
h = Segment(C, B)
a = 3.5 (slider from 0 to 4, step 0.1)
d = Circle(B_1, a)
A = Intersect(c, d, 1)
γ = Angle(B, S, A)
δ = Angle(A, C, B)
f = Segment(C, A)
i = Segment(S, A)