b \cdot \cos \alpha

A = (-1, -1)
B = (6, 1)
C = (-1, 4)
Vieleck1, c, a, b = Polygon(A, B, C)
d = OrthogonalLine(C, a)
e = OrthogonalLine(B, a)
f = OrthogonalLine(B, c)
g = OrthogonalLine(A, c)
h = OrthogonalLine(A, b)
i = OrthogonalLine(C, b)
k = Circle(B, C)
p = Circle(C, B)
q = Circle(B, A)
r = Circle(A, B)
s = Circle(A, C)
t = Circle(C, A)
D = Intersect(t, i, 1.0)
E = Intersect(s, h, 1.0)
F = Intersect(q, f, 1.0)
G, H = Intersect(r, g)
I = Intersect(k, e, 1.0)
J, K = Intersect(p, d)
Vieleck2, c_1, b_1, i_1, j = Polygon(C, B, I, J)
Vieleck3, c_2, d_1, e_1, a_1 = Polygon(C, D, E, A)
Vieleck4, a_2, g_1, f_1, b_2 = Polygon(A, G, F, B)
l = OrthogonalLine(C, c)
L = Intersect(l, c)
h_1 = Circle(A, L)
M, O = Intersect(h_1, a_2)
m = OrthogonalLine(M, a_2)
N = Intersect(m, f_1)
n = Segment(L, C)
Vieleck5, a_3, m_1, n_1, b_3 = Polygon(A, M, N, B)
j_1 = Line(M, N)
A' = Mirror(A, j_1)
M' = Mirror(M, j_1)
N' = Mirror(N, j_1)
B' = Mirror(B, j_1)
Vieleck5', a', m', n', b' = Polygon(A', M', N', B')
Vieleck6, a'_1, g_2, f_2, b'_1 = Polygon(A', G, F, B')
k_1 = Segment(A, L)
α = Angle(B, A, C)