5x2 +3x -2 = 0
ax2 bx c = 0
a = 5
b = 3
c = -2
Δ = b2-4ac
Δ = 3² - (4 * 5 * -2)
Δ = 9 - (4*-10)
Δ = 9 - (-40)
Δ = 49 Δ > 0
5x2+3x-2=0
x = -b ∓ √Δ 2a
x' = -3 - √49 2*5 = -3 - 7.0 10 = -10.0 10 = -1.0
x" = -3 + √49 2*5 = -3 + 7.0 10 = 4.0 10 = 0.4
x' = -25.0
x" = 10.0
S = {x ∈ R / x' = -25.0, x" = 10.0 }