-4x2 +11x +3 = 0
ax2 bx c = 0
a = -4
b = 11
c = 3
Δ = b2-4ac
Δ = 11² - (4 * -4 * 3)
Δ = 121 - (4*-12)
Δ = 121 - (-48)
Δ = 169 Δ > 0
-4x2+11x+3=0
x = -b ∓ √Δ 2a
x' = -11 - √169 2*-4 = -11 - 13.0 -8 = -24.0 -8 = 3.0
x" = -11 + √169 2*-4 = -11 + 13.0 -8 = 2.0 -8 = -0.25
x' = 48.0
x" = -4.0
S = {x ∈ R / x' = 48.0, x" = -4.0 }