Найдите знаменатель и шестой член геометрической прогрессии 72, 12, 2, ….

Ответ:

\[72,\ 12,\ 2,\ \ldots\]

\[q = \frac{2}{12} = \frac{1}{6};\]

\[b_{6} = b_{1} \cdot q^{5} = \frac{72}{6^{5}} = \frac{6^{2} \cdot 2}{6^{5}} =\]

\[= \frac{2}{6^{3}} = \frac{2}{216} = \frac{1}{108}.\]