\[{x^6} + 9{x^3} + 8 = 0\]

\[\left( {x - 1} \right)\left( {x + 1} \right)\left( {x - 3} \right)\left( {x + 3} \right) = 105\]

\[\frac{{2{x^2} - 5x + 4}}{{3x - 2}} + \frac{{15x - 10}}{{2{x^2} - 5x + 4}} = 6\]