Question

Resolva as equações do 2 grau
A)5x^2=x
B)9x2=5x

Answer 1

A)   5x² = x ------> 5x² - x = 0          x( 5x - 1) = 0      x' = 0  e  x - 1 = 0 ∴ x" = 1

S = { 0 , 1 }

B)  9x² = 5x ------>   9x² - 5x = 0 ----->  x(9x - 5) = 0       x' = 0     9x" - 5 = 0

9x" = 5   ---->  x" = 5/9

S = { 5/9 }

Answer 2

A)
5x2=x
5x2-x=0
a=5 b=-1 c=0

/\=b(2)-4.a.c
/\=(-1)(2)-4.5.0
/\=1-0
/\=1

x=-b+-{raiz de /\}/2.a
x=1+- {raiz de 1}/2.5
x=1+-1/10
x'=1+1/10=2/10=1/5
x''=1-1/10=0/10=0

S={1/5,0}

B)
9x2=5x
9x2-5x=0
a=9 b=-5 c=0

/\=(-5)(2)-4.9.0
/\=25-0
/\=25

x=5+-{raiz de 25}/2.9
x=5+-5/18
x'=5+5/18=10/18=5/9
x''=5-5/18=0/18=0

S={5/9,0}