-3x2 +12x -9 = 0
ax2 bx c = 0
a = -3
b = 12
c = -9
Δ = b2-4ac
Δ = 12² - (4 * -3 * -9)
Δ = 144 - (4*27)
Δ = 144 - (108)
Δ = 36 Δ > 0
-3x2+12x-9=0
x = -b ∓ √Δ 2a
x' = -12 - √36 2*-3 = -12 - 6.0 -6 = -18.0 -6 = 3.0
x" = -12 + √36 2*-3 = -12 + 6.0 -6 = -6.0 -6 = 1.0
x' = 27.0
x" = 9.0
S = {x ∈ R / x' = 27.0, x" = 9.0 }