22x2 +21x -1 = 0
ax2 bx c = 0
a = 22
b = 21
c = -1
Δ = b2-4ac
Δ = 21² - (4 * 22 * -1)
Δ = 441 - (4*-22)
Δ = 441 - (-88)
Δ = 529 Δ > 0
22x2+21x-1=0
x = -b ∓ √Δ 2a
x' = -21 - √529 2*22 = -21 - 23.0 44 = -44.0 44 = -1.0
x" = -21 + √529 2*22 = -21 + 23.0 44 = 2.0 44 = 0.0454545454545
x' = -484.0
x" = 22.0
S = {x ∈ R / x' = -484.0, x" = 22.0 }