What is [math]\sqrt {2+\sqrt {2+\sqrt {2+\sqrt {2+...\infty}}}}[/math] ?
If [math]y=f(x)=\sqrt{x+\sqrt{x^2+\sqrt{x+\sqrt{x^2+\sqrt{...\infty}}}}}[/math] and [math]\int f'(x)dy=g(y)+c[/math]. Then what is [math]g[/math]?