A = (-1.5, 0)
r = 1
180°: A - (r, 0)
90°: A + (0, r)
270°: A - (0, r)
g = Segment(270°, 90°)
c = Circle(A, r)
0°: A + (1, 0)
h = Segment(180°, 0°)
P = Point(c)
α = Angle(0°, A, P)
a = Segment(A, P)
b = Segment(A, 0°)
d = OrthogonalLine(P, b)
D = Intersect(d, b)
sin(α) = Segment(P, D)
cos(α) = Segment(A, D)
i = OrthogonalLine(0°, h)
C = Intersect(a, i)
tan(α) = Segment(0°, C)
j = Segment(C, A)