Rozlož na súčin výraz \( 8 r^{3}-s^{3} \).
\( =(2 r-s) \cdot\left(4 r^{2}+2 r s+s^{2}\right) \)
\( =(2 r+s) \cdot\left(4 r^{2}-2 r s+s^{2}\right) \)
\( =(2 r-s) \cdot\left(4 r^{2}-2 r s-s^{2}\right) \)
\( =(2 r-s) \cdot\left(4 r^{2}+2 r s-s^{2}\right) \)