Az x^2=y*(y-1)*(y-c) harmadrendű görbe

c = -1.9 (slider from -5 to 5, step 0.1)
A = Point(yAxis)
f(x) = x^(2.0) - y(A) * (y(A) - 1.0) * (y(A) - c)
B, C = Intersect(f, xAxis)
a = Line(A, xAxis)
b = OrthogonalLine(B, xAxis)
d = OrthogonalLine(C, xAxis)
D = Intersect(b, a)
E = Intersect(d, a)
ponthalmaz1 = Locus(E, A)
ponthalmaz2 = Locus(D, A)