12x2 +6x -6 = 0
ax2 bx c = 0
a = 12
b = 6
c = -6
Δ = b2-4ac
Δ = 6² - (4 * 12 * -6)
Δ = 36 - (4*-72)
Δ = 36 - (-288)
Δ = 324 Δ > 0
12x2+6x-6=0
x = -b ∓ √Δ 2a
x' = -6 - √324 2*12 = -6 - 18.0 24 = -24.0 24 = -1.0
x" = -6 + √324 2*12 = -6 + 18.0 24 = 12.0 24 = 0.5
x' = -144.0
x" = 72.0
S = {x ∈ R / x' = -144.0, x" = 72.0 }