[tex]\displaystyle\\
\bf\\
\text{Amplificam cu conjugatul numitorului }\\
~~~~~~~~~( \sqrt{2}+1 ) \\
\text{pentru a rationaliza numitorul.}\\\\
\texttt{Rezolvare:}\\\\
b= \frac{\sqrt{2}+1 }{\sqrt{2}-1 } = \frac{(\sqrt{2}+1)(\sqrt{2}+1) }{(\sqrt{2}-1)(\sqrt{2}+1) } = \frac{(\sqrt{2}+1)^2 }{2-1 } = \boxed{\bf (\sqrt{2}+1)^2}[/tex]
