Ответ:
\(\dfrac{p^{-7}\cdot p^{-19}}{p^{-21}}=p^{-7-19-(-21)}=p^{-5}\).
При \(p=5\): \(5^{-5}=\dfrac{1}{5^5}=\dfrac{1}{3125}\).
Ответ: \(\dfrac{1}{3125}\).
\(\dfrac{p^{-7}\cdot p^{-19}}{p^{-21}}=p^{-7-19-(-21)}=p^{-5}\).
При \(p=5\): \(5^{-5}=\dfrac{1}{5^5}=\dfrac{1}{3125}\).
Ответ: \(\dfrac{1}{3125}\).