-4x2 -4x +8 = 0
ax2 bx c = 0
a = -4
b = -4
c = 8
Δ = b2-4ac
Δ = -4² - (4 * -4 * 8)
Δ = 16 - (4*-32)
Δ = 16 - (-128)
Δ = 144 Δ > 0
-4x2-4x+8=0
x = -b ∓ √Δ 2a
x' = 4 - √144 2*-4 = 4 - 12.0 -8 = -8.0 -8 = 1.0
x" = 4 + √144 2*-4 = 4 + 12.0 -8 = 16.0 -8 = -2.0
x' = 16.0
x" = -32.0
S = {x ∈ R / x' = 16.0, x" = -32.0 }