Respostas

2013-05-23T14:35:30-03:00

x² - 5x + 8 = 0

\Delta = (-5)² - 4 . 1 . 8 

   ''  = 25 - 32

   '' = - 7

 

x1 = 5 + \sqrt {7}i / 2 . 1

x1 = \frac{5}{2} + \frac{\sqrt{7}i}{2}

 

x2 = 5 - \sqrt {7}i / 2 . 1

x2 = \frac{5}{2} - \frac{\sqrt{7}i}{2}