Respuesta :
[tex]0=-x^2+2x+1\\x^2-2x-1=0\\x=\frac{-(-2)\pm\sqrt{(-2)^2-(4\times1\times-1)}}{2\times1}\\=\frac{2\pm\sqrt{4+4}}{2}\\=\frac{2\pm2\sqrt{2}}{2}\\=1+\sqrt{2} \ or \ 1-\sqrt{2}[/tex]
Therefore, the positive solution is [tex]1+\sqrt{2}[/tex]
Therefore, the positive solution is [tex]1+\sqrt{2}[/tex]