-1x2 +7x -6 = 0
ax2 bx c = 0
a = -1
b = 7
c = -6
Δ = b2-4ac
Δ = 7² - (4 * -1 * -6)
Δ = 49 - (4*6)
Δ = 49 - (24)
Δ = 25 Δ > 0
-x2+7x-6=0
x = -b ∓ √Δ 2a
x' = -7 - √25 2*-1 = -7 - 5.0 -2 = -12.0 -2 = 6.0
x" = -7 + √25 2*-1 = -7 + 5.0 -2 = -2.0 -2 = 1.0
x' = 6.0
x" = 1.0
S = {x ∈ R / x' = 6.0, x" = 1.0 }