Resposta :
[tex]x^2 - (1 + \sqrt{2})x + \sqrt{2} = 0 \\ x^2 - x - x\sqrt{2} + \sqrt{2} = 0 \\ x(x - 1) - \sqrt{2}(x - 1) = 0 \\ (x - 1)[x - \sqrt{2}] = 0 \\ (x - 1)(x - \sqrt{2}) = 0 \\\\ \begin{cases} x - 1 = 0 \Rightarrow \boxed{x = 1} \\ x - \sqrt{2} = 0 \Rightarrow \boxed{x = \sqrt{2}} \end{cases} \\\\ \boxed{\boxed{S = \left \{ 1, \sqrt{2} \right \}}}[/tex]