Question

Apresente+a+solução+das+equações:
A) x^2-4x+3=0
B) x^2+9x+8=0
C) -x^2+6x-5=0

Answer 1

A) x^2-4x+3=0

a=1

b=-4

c=3

∆=b²-4.a.c

∆=(-4)²-4.(1).(3)

∆=16-12

∆=4

x'=[-(-4)+√4]/2.(1)

x'=[4 +2]/2

x'=6/2

x'=3

x"=[-(-4)-√4]/2.(1)

x"=[4-2]/2

x"=2/2

x"=1

S={( 1 : 3)}

B) x^2+9x+8=0

a=1

b=9

c=8

∆=b²-4.a.c

∆=(9)²-4.(1).(8)

∆=81-32

∆=49

x'=[-(+9)+√49]/2.(1)

x'=[-9+7]/2

x'=-2/2

x'=-1

x"=[-(+9)-√49]/2.(1)

x"=[-9-7]/2

x"=-16/2

x"=-8

S={( -8 : -1)}

C) -x^2+6x-5=0

a=-1

b=6

c=-5

∆=b²-4.a.c

∆=(6)²-4.(-1).(-5)

∆=36-20

∆=16

x'=[-(+6)+√16]/2.(-1)

x'=[-6+4]/-2

x'=-2/-2

x'=1

x"=[-(+6)-√16]/2.(-1)

x"=[-6-4]/-2

x"=-10/-2

x"=5

S={( 1 : 5)}