-3x2 +3x +6 = 0
ax2 bx c = 0
a = -3
b = 3
c = 6
Δ = b2-4ac
Δ = 3² - (4 * -3 * 6)
Δ = 9 - (4*-18)
Δ = 9 - (-72)
Δ = 81 Δ > 0
-3x2+3x+6=0
x = -b ∓ √Δ 2a
x' = -3 - √81 2*-3 = -3 - 9.0 -6 = -12.0 -6 = 2.0
x" = -3 + √81 2*-3 = -3 + 9.0 -6 = 6.0 -6 = -1.0
x' = 18.0
x" = -9.0
S = {x ∈ R / x' = 18.0, x" = -9.0 }