Question

resolva as equacoes do do 2° grau​

Answer 1

Explicação passo-a-passo:

a) x² - 2x + 1 = 0

a= 1; b = -2; c = 1

D = -2² - 4 . 1 . 1

D = 4 - 4

D = 0

x' = (-(-2) + 0)/(2 . 1)

x' = (2 + 0)/(2)

x' = (2)/(2)

x' = 1

x" = (-(-2) - 0)/(2 . 1)

x" =( 2 - 0)/( 2)

x'' = (2)/( 2)

x'' = 1

S = {(1, 1)}

b) x² + x - 6 = 0

a = 1; b = 1; c = -6

D = 1² - 4 . 1 . (-6)

D = 1 + 24

D = 25

x' = (-1 + 5)/(2 . 1)

x' = (-1 + 5)/(2)

x' = (4)/(2)

x' = 2

x" = (-1 - 5)/(2 . 1)

x" =( -1 - 5)/( 2)

x'' = (-6)/( 2)

x'' = -3

S = {(-3, 2)}

c) 2x² + 4x - 6 = 0

a = 2; b = 4; c = -6

D = 4² - 4 . 2 . (-6)

D = 16 + 48

D = 64

x' = (-4 + 8)/(2 . 2)

x' = (-4 + 8)/(4)

x' = (4)/(4)

x' = 1

x" = (-4 - 8)/(2 . 2)

x" =( -4 - 8)/( 4)

x'' = (-12)/( 4)

x'' = -3

S = {(-3, 1)}

d) x² - 10x + 25 = 0

a = 1; b = -10; c = 25

D = (-10)² - 4 . 1 . 25

D = 100 - 100

D = 0

x' = (-(-10) + 0)/(2 . 1)

x' = (10 + 0)/(2)

x' = (10)/(2)

x' = 5

x" = (-(-10) - 0)/(2 . 1)

x" =( 10 - 0)/( 2)

x'' = (10)/( 2)

x'' = 5

S = {(5, 5)}

e) 2x² - 5x - 7 = 0

a = 2; b = -5; c = -7

D = (-5)² - 4 . 2 . (-7)

D = 25 + 56

D = 81

x' = (-(-5) + 9)/(2 . 2)

x' = (5 + 9)/(4)

x' = (14)/(4)

x' = 7/2

x" = (-(-5) - 9)/(2 . 2)

x" =( 5 - 9)/( 4)

x'' = (-4)/( 4)

x'' = -1

S = {(-1, 7/2)}