simplify the following radical expressions using rationalization.

[tex]1. \frac{ \sqrt{7} }{7} \\ 2. \: \frac{ \sqrt{15} }{5} \\ 3. \frac{ \sqrt{ab} }{b} \\ 4. \: \frac{|x| \sqrt{3} }{6} \\ 5. \: \sqrt[3] \frac{3}{3} [/tex]