-12x2 +20x -8 = 0
ax2 bx c = 0
a = -12
b = 20
c = -8
Δ = b2-4ac
Δ = 20² - (4 * -12 * -8)
Δ = 400 - (4*96)
Δ = 400 - (384)
Δ = 16 Δ > 0
-12x2+20x-8=0
x = -b ∓ √Δ 2a
x' = -20 - √16 2*-12 = -20 - 4.0 -24 = -24.0 -24 = 1.0
x" = -20 + √16 2*-12 = -20 + 4.0 -24 = -16.0 -24 = 0.666666666667
x' = 144.0
x" = 96.0
S = {x ∈ R / x' = 144.0, x" = 96.0 }