y = ax² + bx + c

a = 0.6 (slider from -10 to 10, step 0.1)
b = -3.1 (slider from -10 to 10, step 0.1)
c = 0.8 (slider from -10 to 10, step 0.1)
d: y = a * x^(2) + b * x + c
S = Vertex(d)
C = Intersect(d, yAxis, 1)
texte2: "" + d + ""

Tool: Outil1
Input: E, F, H
Output: γ

a = Segment(E, F)
G = Point(a)
α = Angle(E, G, H)
β = Angle(H, G, F)
γ: α + β