oblicz
a)
[tex]( \sqrt{5 } \ + 2)( \sqrt{5} - 2)[/tex]
b)
[tex]( \sqrt{5} - \sqrt{2)} ( \sqrt{2} + 3 \sqrt{5)} [/tex]
c)
[tex](5 + \sqrt{2)} ( \sqrt{8} - 1) - 9 \sqrt{2} (1 + \sqrt{2)} [/tex]