Area (α)=%y

g(x) = 5 * sin(x) + 1 / 4 * sqrt((29 - 20 * cos(x)) * (-13 + 20 * cos(x)))
p = If(0 < x / 4 < 1.5708, g(x / 4))
G = Point(p)
A = (8, 3)
B = (13, 3)
c = Circle(A, 2)
C: (x(A) + 2 * cos(x(G) / 4), y(A) + 2 * sin(x(G) / 4))
d = Circle(B, 2)
e = Circle(C, 2)
D, E = Intersect(e, d)
poly1, a, b, d_1, c_1 = Polygon(A, B, D, C)
α = Angle(B, A, C)
f = Segment((x(A) - 2, y(C)), (x(B) + 2, y(C)))
h = 0.7227342478134156
F: (4 * h, g(h))
i = Segment((x(F) - 1, y(F)), (x(F) + 1, y(F)))