log x (x+2)=2
c.e. {x>0=> x€(0,+∞) {x≠1 {x+2>0=>x>–2=>x€(–2,+∞)
=> D=(0,+∞)\{1} x²=x+2=>x²–x–2=0
a=1; b=–1, c=–2
∆=b²–4ac=(–1)²–4·1·(–2)=1+8=9 x1,2=(–b±√∆)/2a=(1±√9)/2=(1±3)/2
x1=(1+3)/2=4/2=2€D
x2=(1–3)/2=–2/2=–1 €/ D (adică nu aparține lui D) S={2}
