Respostas

2013-08-18T16:43:50-03:00
x²+6x+8= 0
a = 1;b = 6;c = 8

D = b^2 -4.a.c
D = 6^2 - 4.1.8
D = 36 - 32 = 4
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x' =  \frac{- b +  \sqrt{D} }{2.a}
x' =  \frac{- 6 +  \sqrt{4} }{2.1}
x' =  \frac{- 6 + 2}{2}
x' =  \frac{- 4 }{2}
x' = -2
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x" =  \frac{- b  -  \sqrt{D} }{2.a}
x" =  \frac{- 6 - 2}{2}
x" =  \frac{- 8}{2}
x" = -4