-6x2 +13x +19 = 0
ax2 bx c = 0
a = -6
b = 13
c = 19
Δ = b2-4ac
Δ = 13² - (4 * -6 * 19)
Δ = 169 - (4*-114)
Δ = 169 - (-456)
Δ = 625 Δ > 0
-6x2+13x+19=0
x = -b ∓ √Δ 2a
x' = -13 - √625 2*-6 = -13 - 25.0 -12 = -38.0 -12 = 3.16666666667
x" = -13 + √625 2*-6 = -13 + 25.0 -12 = 12.0 -12 = -1.0
x' = 114.0
x" = -36.0
S = {x ∈ R / x' = 114.0, x" = -36.0 }