Odpowiedź:
[tex]\dfrac{13}{4+\sqrt{3}}=\dfrac{13}{4+\sqrt{3}}*\dfrac{4-\sqrt{3}}{4-\sqrt{3}}=\dfrac{13(4-\sqrt{3})}{(4+\sqrt{3})(4-\sqrt{3})}=\dfrac{13(4-\sqrt{3})}{4^2-(\sqrt{3})^2}=\\\\\\=\dfrac{13-(4\sqrt{3})}{16-3}=\dfrac{\not13(4-\sqrt{3})}{\not13}=4-\sqrt{3}[/tex]
