-3x2 +9x -6 = 0
ax2 bx c = 0
a = -3
b = 9
c = -6
Δ = b2-4ac
Δ = 9² - (4 * -3 * -6)
Δ = 81 - (4*18)
Δ = 81 - (72)
Δ = 9 Δ > 0
-3x2+9x-6=0
x = -b ∓ √Δ 2a
x' = -9 - √9 2*-3 = -9 - 3.0 -6 = -12.0 -6 = 2.0
x" = -9 + √9 2*-3 = -9 + 3.0 -6 = -6.0 -6 = 1.0
x' = 18.0
x" = 9.0
S = {x ∈ R / x' = 18.0, x" = 9.0 }