15x2 +2x -17 = 0
ax2 bx c = 0
a = 15
b = 2
c = -17
Δ = b2-4ac
Δ = 2² - (4 * 15 * -17)
Δ = 4 - (4*-255)
Δ = 4 - (-1020)
Δ = 1024 Δ > 0
15x2+2x-17=0
x = -b ∓ √Δ 2a
x' = -2 - √1024 2*15 = -2 - 32.0 30 = -34.0 30 = -1.13333333333
x" = -2 + √1024 2*15 = -2 + 32.0 30 = 30.0 30 = 1.0
x' = -255.0
x" = 225.0
S = {x ∈ R / x' = -255.0, x" = 225.0 }