-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 = 784 Δ > 0
-12x2+20x+8=0
x = -b ∓ √Δ 2a
x' = -20 - √784 2*-12 = -20 - 28.0 -24 = -48.0 -24 = 2.0
x" = -20 + √784 2*-12 = -20 + 28.0 -24 = 8.0 -24 = -0.333333333333
x' = 288.0
x" = -48.0
S = {x ∈ R / x' = 288.0, x" = -48.0 }