r = 2.2486440358580557 (slider from 0 to 4, step 0.01)
α = 2.362483715445052 rad (slider from 0 to 6.283185307179586, step 0.017453292519943295)
A = (0, 0)
c = Circle(A, 4.0)
B: (r; α)
C = Point(c)
a = Segment(B, C)
b = Tangent(C, c)
d = OrthogonalLine(C, b)
e = LineBisector(B, C)
D = Intersect(d, e)
f = Circle(D, C)
loc1 = Locus(D, C)