Ответ:
Подставим \(a=\frac15\):
\[a(a-5)^2=\frac15\left(\frac15-5\right)^2=\frac15\left(-\frac{24}{5}\right)^2=\frac15\cdot\frac{576}{25}=\frac{576}{125}.\]
Ответ: \(\frac{576}{125}\).
Подставим \(a=\frac15\):
\[a(a-5)^2=\frac15\left(\frac15-5\right)^2=\frac15\left(-\frac{24}{5}\right)^2=\frac15\cdot\frac{576}{25}=\frac{576}{125}.\]
Ответ: \(\frac{576}{125}\).