Question

Determine o zero da função -x² + x + 2

Answer 1

-x² + x + 2 = 0
a = -1    b = 1     c = 2
Δ = 1² - 4 x -1 x 2
Δ = 1 + 8 = 9
x = -1 +- √9/2 x -1
x = -1 +- 3/-2
x1 = -1 + 3/ -2  = 2/-2 = -1
x2 = -1-3 /-2    = -4/-2 = +2