Odpowiedź:
[tex]\dfrac{3}{\sqrt{5}+2}=\dfrac{3}{\sqrt{5}+2}\cdot\dfrac{\sqrt{5}-2}{\sqrt{5}-2}=\dfrac{3(\sqrt{5}-2)}{(\sqrt{5}+2)(\sqrt{5}-2)}=\dfrac{3\sqrt{5}-6}{(\sqrt{5})^2-2^2}=\dfrac{3\sqrt{5}-6}{5-4}=\\\\\\=\dfrac{3\sqrt{5}-6}{1}=3\sqrt{5}-6[/tex]
