[tex]2x^3 - 4x^2 + x - 1 = \\\\ 2 \cdot \left ( \frac{1}{3} \right )^3 - 4 \cdot \left ( \frac{1}{3} \right )^2 + \left ( \frac{1}{3} \right ) - 1 = \\\\ 2 \cdot \left ( \frac{1}{27} \right ) - 4 \cdot \left ( \frac{1}{9} \right ) + \frac{1}{3} - 1 = \\\\ \frac{2}{27} - \frac{4}{9} + \frac{1}{3} - 1 = \\\\ \frac{2 \cdot 1 - 4 \cdot 3 + 1 \cdot 9 - 1 \cdot 27}{27} \\\\ \frac{2 - 12 + 9 - 27}{27} \\\\ \boxed{\frac{- 28}{27}}[/tex]
