Question

Utilizando A formula resolutiva (Bhaskara) Encontre as raízes das equações do 2° Grau:


A) x^2 - x - 6 = 0

B) x^2 +2x - 3 = 0​

Answer 1

a) x² - x - 6 = 0

a = 1

b = - 1

c = - 6

∆ = b² - 4 . a . c

∆ = (-1)² - 4 . 1 . (-6)

∆ = 1 + 24

∆ = 25

x = - b ± √∆

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2a

x' = - (-1) - 5

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2 . 1

x' = 1 - 5

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2

x' = - 4

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2

x' = - 2

x" = - (-1) + 5

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2 . 1

x" = 1 + 5

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2

x" = 6

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2

x" = 3

S = {-2 , 3}

b) x² + 2x - 3 = 0

a = 1

b = 2

c = - 3

∆ = b² - 4 . a . c

∆ = 2² - 4 . 1 . (-3)

∆ = 4 + 12

∆ = 16

x = - b ± √∆

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2a

x' = - 2 - 4

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2 . 1

x' = - 6

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2

x' = - 3

x" = - 2 + 4

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2 . 1

x" = 2

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2

x" = 1

S = {-3 , 1}