[tex]L = (\frac{2}{3})^{2} - (\frac{2}{3}) = \frac{4}{9} - \frac{2}{3} = \frac{4}{9} - \frac{6}{9} = -\frac{2}{9}[/tex]
[tex]P = (\frac{2}{3})^3 - 1 = \frac{8}{27} - 1 = \frac{8}{27} - \frac{27}{27} = -\frac{19}{27}[/tex]
[tex]-\frac{2}{9} = -\frac{6}{27}[/tex]
[tex]L\neq P[/tex], więc liczba [tex]\frac{2}{3}[/tex] nie spełnia tego równania.
