Respostas

  • Usuário do Brainly
2013-06-19T17:49:26-03:00

Temos que:

 

3\text{x}^2+5\text{x}-2=0

 

\text{x}=\dfrac{-5\pm\sqrt{5^2-4\cdot3\cdot(-2)}}{2\cdot3}=\dfrac{-5\pm7}{6}

 

Logo, as raízes são:

 

\text{x}'=\dfrac{-5+7}{6}=\dfrac{1}{3}

 

\text{x}"=\dfrac{-5-7}{6}=-2

 

Desta maneira, \text{S}=\{-2, \frac{1}{3}\}