Question

5 me ao quadrado -9m+4 =0

X ao quadrado -6 +7=0

X ao quadrado -4x+1=0

Answer 1

5 m^2 - 9m + 4 = 0

a = 5; b = - 9; c = 4

∆ = b^2-4ac

∆ = (-9)^2 - 4.5.4

∆ = 81 - 80

∆ = 1

x = [ - b +/- √∆]/2a

x = [- (-9) +/- √1]/2.5

x = (9 +/- 1]/10

x ' = (9+1)/10 = 10/10 = 1

x " = (9-1)/10 = 8/10 (:2)/(:2) = 4/5

X^2 - 6x +7 = 0

a = 1; b = - 6; c = 7

∆ = b^2-4ac

∆ = (-6)^2 - 4.1.7

∆ = 36 - 28

∆ = 8

√∆ = √8 = √4.√2 = 2√2

x = [ - b +/- √∆]/2a

x = [- (-6) +/- √8]/2.1

x = (6 +/- 2√2)/2

x = (6/2 +/- 2√2)/2

x' = 3 + √2

x" = 3 - √2

X^2 -4x + 1 = 0

a = 1; b = - 4; c = 1

∆ = b^2-4ac

∆ = (-4)^2 - 4.1.1

∆ = 16 - 4

∆ = 12

√∆ = √12 = √4.√3 = 2√3

x = [ - b +/- √∆]/2a

x = [ -(-4) +/- √12]/2.1

x = [4 +/- 2√3]/2

x = [4/2 +/- 2√3/2]

x' = 2 + √2

x" = 2 - √2