Răspuns:
[tex]a \: = \sqrt{5} - \sqrt{3} [/tex]
[tex]b = 4 \sqrt{3} - 3 \sqrt{5} [/tex]
3a-b =
[tex]3 \sqrt{5} - 3 \sqrt{3} - 4 \sqrt{3} + 3 \sqrt{5} = - 7 \sqrt{3} + 6 \sqrt{5} [/tex]