Respostas

2013-12-12T16:16:06-02:00
9x²-1=3x-x² 
10x
²-3x-1=0
aplicando bháskara 
Δ=b²-4ac
Δ=9-4(10)(-1)
Δ=9+40=49=

X'=-b+√49/2*10
X'=3+7/20

X'=1/2

X''=3-7/20
X''=-4/20
X''=-1/5


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