Question

Resolva as equações do 2°grau:

a)3x² - 7x +2 = 0

b)6x²+x -1 = 0

c)-x²+6x -5 = 0​

Answer 1

Resposta:

a)
3x² -7x + 2= 0
Delta=49-24
Delta=25
x=-(-7)±raiz quadrada de 25
x=(7±5)/6
x'=7+5/6
x'=12/6
x'=2
x"=(7-5)/6
x"=2/6
x"=1/3

b)

6x² - x - 1 = 0

a = 6
b = -1
c = -1

delta
d² = 1 + 24 = 25
d = 5

x'= (1 + 5)/12 = 6/12 = 1/2
x''= (1 - 5)/12 = -4/12 = -1/3

c)
-x²+6x-5=0

a=-1
b=6
c=-5

delta= 36-20=16

x=(-6+-4)/-2

x=-10/-2=5

x=-2/-2=1

S={1,5}

Espero ter ajudado ^^