6.
$$f ( x ) = x ^ { \frac { 3 } { 2 } } - 8 x ^ { - \frac { 1 } { 2 } }$$
- Evaluate \(\mathrm { f } ( 3 )\), giving your answer in its simplest form with a rational denominator.
- Solve the equation \(\mathrm { f } ( x ) = 0\), giving your answers in the form \(k \sqrt { 2 }\).