Question

Resolva as equações do segundo grau em R:
A) x²-5x+6=0
B) x²-8x+12=0
C) x²+2x-8=0
D) x²-5x+8=0

Answer 1

1.

a) x² - 5x + 6

Δ = b² - 4. a.c

Δ = 25 - 4 . 1. 6

Δ = 1

x₁ =  -b + √Δ /2 a

x₁ = - (-5) + 1 /2

x₁ = 6 / 2

x₁ = 3

x₂ = - b - √Δ / 2a

x₂ = - (-5) - 1 / 2

x₂ = 2


b) x² - 8x + 12 = 0

Δ = 8² - 4.1. 12

Δ = 64 - 48

Δ = 16

x₁ = - b + √Δ / 2a

x₁ = 8 + 4 / 2

x₁ = 6

x₂ = -b - √Δ / 2a

 x₂ = 8 - 4 / 2

x₂ = 2


c) x² + 2x - 8 = 0

Δ = b² - 4 . a . c

Δ = 4 - 4 . 1. -8

Δ = 36

x₁ = - b + √ Δ / 2a

x₁ = - 2 + 6 / 2

x₁ = 2

x₂ = - b - √Δ / 2a

x₂ = - 2 - 6 / 2

x₂ = - 4

d) x² - 5x + 8 = 0

Δ = b² - 4ac

Δ = 25 - 24

Δ = 1

x₁ = - b +√Δ / 2a

x₁ = 5 + 1 / 2

x₁ = 3

x₂ = -b - √Δ / 2a

x₂ = 5 - 1 / 2

x₂ = 4


Espero ter ajudado