Question

resolva as equações:

a) 7x² + 13x - 2 =0
b) x² - 6x + 8 = 0
c) 2x² - 5x + 3 =0​

Answer 1

Resposta:

A. x' = 1/7

x'' = -2

B. x' = 4

x'' = 2

C. x' = 3/2

x'' = 1

Explicação passo-a-passo:

a) 7x² + 13x - 2 = 0

Δ = 13² - 4.7.(-2)

Δ = 169 + 56

Δ = 225

-13 ± √225/2.7

x' = -13 + 15/14

x' = 2/14

x' = 1/7

x'' = -13 - 15/14

x'' = -28/14

x'' = -2

B. x² - 6x +8 = 0

Δ = (-6)² - 4.1.8

Δ = 36 - 32

Δ = 4

6 ± √4/2.1

x' = 6 + 2/2

x' = 8/2

x' = 4

x'' = 6 - 2/2

x'' = 4/2

x'' = 2

C. 2x² - 5x + 3 = 0

Δ = (-5)² - 4.2.3

Δ = 25 - 24

Δ = 1

5 ± √1 /2.2

x' = 5 + 1/4

x' = 6/4

x' = 3/2

x'' = 5 - 1/4

x'' = 4/4

x'' = 1