\[\frac{5x^{3} - 125x}{2x^{3} - 20x^{2} + 50x};\ если\ x = 6.\]
\[\frac{5x^{3} - 125x}{2x^{3} - 20x^{2} + 50x} =\]
\[= \frac{5 \cdot (x + 5)}{2 \cdot (x - 5)} = \frac{5 \cdot (6 + 5)}{2 \cdot (6 - 5)} =\]
\[= \frac{5 \cdot 11}{2 \cdot 1} = \frac{55}{2} = 27,5.\]