Question

Как сократить эту дробь?

Answer 1

    (17+2√30)(√15 -√2)                 17√15-17√2+30√2-4√15

=_______________________=______________________=

      (√15+√2)(√15-√2)                     (√15)² -(√2)²

13√15+13√2          13(√15+√2)

=___________=________________=√15+√2

      15-2                        13

Answer 2

 $\frac{17+2 \sqrt{30} }{ \sqrt{15} + \sqrt{2} } = \frac{( \sqrt{15}+ \sqrt{2})^2 }{ \sqrt{15} + \sqrt{2} }= \sqrt{15}+ \sqrt{2}$


P. S.
$17+2 \sqrt{30}=15+2+2 \sqrt{30} =( \sqrt{15})^2+( \sqrt{2})^2+2* \sqrt{15}* \sqrt{2}=$$( \sqrt{15}+ \sqrt{2} )^2$