-6x2 +15x -6 = 0
ax2 bx c = 0
a = -6
b = 15
c = -6
Δ = b2-4ac
Δ = 15² - (4 * -6 * -6)
Δ = 225 - (4*36)
Δ = 225 - (144)
Δ = 81 Δ > 0
-6x2+15x-6=0
x = -b ∓ √Δ 2a
x' = -15 - √81 2*-6 = -15 - 9.0 -12 = -24.0 -12 = 2.0
x" = -15 + √81 2*-6 = -15 + 9.0 -12 = -6.0 -12 = 0.5
x' = 72.0
x" = 18.0
S = {x ∈ R / x' = 72.0, x" = 18.0 }