Respostas

2014-07-15T05:02:12-03:00
2z² - z - 1 = 0

Δ = b² - 4.a.c
Δ = (-1)² - 4. 2. (-1)
Δ = 1 + 8
Δ = 9

x1 =  \frac{- (-1) +  \sqrt{9} }{2.2}

x1 =  \frac{4}{4}

x1 = 1

x2 = 
 \frac{- (-1) - \sqrt{9} }{2.2}

x2 =  \frac{-2}{4}  

x2 = 
 \frac{-1}{2}