$ \alpha $

$ R $

$ R $

$ R $

$ \frac{\alpha}{2} $

$ \frac{\alpha}{2} $

$ \pi-\alpha $

$ 2\alpha $

$ r $

$ r $

$ a $

C = Intersect(xAxis, yAxis)
B_1 = (4, 0)
c = Circle(C, B_1)
a, b = AngularBisector(yAxis, xAxis)
P, D = Intersect(c, a)
r = 3.827 (slider from 0 to 8, step 0.0010)
d = Circle(D, r)
B, A = Intersect(d, c)
e = Segment(P, A)
f = Segment(P, B)
g = CircleArc(P, B, A)
h = CircleSector(P, B, A)
areah = Area(h)
Testoh: "Area = " + areah
α = Angle(B, P, A)
i = Segment(P, C)
j = Segment(C, A)
k = Segment(C, B)
β = Angle(C, P, A)
γ = Angle(A, C, P)
δ = Angle(P, A, C)
ε = Angle(B, C, A)