Question

me ajudem a encontrar as raizes das equaçoes do 2 grau. usando a formula de bascara x=(b)+ 2x2+4x+2=0 =b2-4.a.c x2-5x+6=0 =b2-4.a.c x2-10x+9=0 =b2-4.a.c x2-6x+8=0 =b2-4.a.c

Answer 1

a)
2x² + 4x + 2 = 0  (:2)
x² + 2x + 1 = 0
a = 1; b = 2; c = 1

Δ = b² - 4ac
Δ = 2² - 4.1.1
Δ = 4 - 4
Δ = 0

x = - b +/- √Δ  = - 2 +/- √0
          2a               2.1

x = - 2  = - 1
        2

R.: x = - 1
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b)
x² - 5x + 6 = 0
a = 1; b = - 5; c = 6

Δ = b² - 4ac
Δ = (-5)² - 4.1.6
Δ = 25 - 24
Δ = 1

x = - b +/- √Δ  = - ( - 5) +/- √1
         2a                 2.1

x = 5 + 1 = 6/2 = 3
        2

x = 5 - 1 = 4/2 = 2
        2

R.: x = 3 e x = 2
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c)
x² - 10x + 9 = 0
a = 1; b = - 10; c = 9

Δ = b² - 4ac
Δ = (-10)² - 4.1.9
Δ = 100 - 36
Δ = 64

x = - b +/- √Δ  = - ( - 10) +/- √64
          2a                      2.1

x = 10 + 8 = 18/2 = 9
         2

x = 10 - 8 = 2/2 = 1
          2

R.: x = 1 e x = 9
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d)
x² - 6x + 8 = 0
a = 1; b = - 6; c = 8

Δ = b² - 4ac
Δ = (-6)² - 4.1.8
Δ = 36 - 32
Δ = 4

x = - b +/- √Δ  = - ( - 6) +/- √4
          2a                  2.1

x = 6 + 2 = 8/2 = 4
         2

x = 6 - 2 = 4/2 = 2
        2

R.: x = 4 e x = 2