\[\boxed{\mathbf{685\ (685).\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[Буква\] | \[а\] | \[е\] | \[и\] | \[б\] | \[н\] | \[о\] | \[р\] | \[у\] | \[ф\] | \[я\] |
---|---|---|---|---|---|---|---|---|---|---|
\[Частота\] | \[17\] | \[23\] | \[12\] | \[3\] | \[14\] | \[22\] | \[14\] | \[5\] | \[0\] | \[7\] |
\[Относит.\ \] \[частота\ \%\] |
\[7,8\] | \[10,6\] | \[5,5\] | \[1,4\] | \[6,4\] | \[10,1\] | \[6,4\] | \[2,3\] | \[0\] | \[3,2\] |
\[Всего\ 218\ букв.\]
\[Мода - буква\ Е.\]
\[\boxed{\mathbf{685.\ }Еуроки\ - \ ДЗ\ без\ мороки}\]
\[1)\ b_{2},\ b_{4},\ \ldots,\ b_{2n}\]
\[\ b_{2} = b_{1}q\]
\[b_{4} = b_{1}q^{3}\ \]
\[b_{2n} = b_{1}q^{2n - 1}\]
\[q = \frac{b_{4}}{b_{2}} = \frac{b_{1}q^{3}}{b_{1}q} =\]
\[= q^{2} \Longrightarrow \ \ является;\]
\[2)\ b_{1}b_{3},\ b_{2}b_{4},\ b_{3}b_{5},\ \ldots,\ b_{n - 2}b_{n}\]
\[q = \frac{b_{1}b_{n}}{b_{1}b_{3}} = \frac{b_{1}qb_{1}q^{3}}{b_{1}b_{1}q^{2}} =\]
\[= q² \Longrightarrow является.\]