Equazioni di secondo grado
Author: Ubaldo Pernigo (UbiMath)

x_1∨x_2 = \frac{-b\pm \sqrt{b^2-4ac}}{2a}

Spuria: \;  x_1 = 0 \vee x_2= \frac{-b}{a}

by UbiMath

a = 7 (slider from -100 to 100, step 0.05)
b = -4 (slider from -100 to 100, step 0.05)
c = -1 (slider from -100 to 100, step 0.05)
f(x) = (a * x^(2)) + (b * x) + c
delta: "Δ=b^2-4ac=" + (LaTeX[b^(2)]) + "-" + (LaTeX[((4 * a) * c)]) + "=" + (LaTeX[b^(2) - (4 * (a * c))]) + ""
X2 = Intersect(f, xAxis, 1)
X1 = Intersect(f, xAxis, 2)
C = Intersect(f, yAxis, 1)
r2: "x_1=" + (LaTeX[((-b) + (b^(2) - ((4 * a) * c))^(0.5)) / ((2 * a))]) + ""
r1: "x_2=" + (LaTeX[((-b) - (b^(2) - ((4 * a) * c))^(0.5)) / ((2 * a))]) + ""
V = Extremum(f)