Question

x2+2x-8 na formula de bhaskara ?

Answer 1

Δ = b² - 4.(a) . (c)
a = 1
b = 2
c = -8
Δ = 1² - 4.1.(-8)
Δ = 36
x = -b +- raíz de Δ/2.a
x' = -2 + 6/2 => 2
x'' = -2 - 6/2 => -4

Answer 2

x² + 2x - 8 = 0

a = 1        b=  +2      c = - 8
Δ = b² - 4.a.c
Δ = (2)² - 4.(1).(-8)
Δ = 4 + 32
Δ = 36


x = - b ± √Δ
         2.a

x = - (+2) ±  √36
            2.1


x = - 2  ±  6
           2


x'= - 2 + 6   =    + 4   =   2
          2               2


x" = - 2 - 6  =  - 8  =   - 4
           2           2


S[- 4, 2]