Решебник по алгебре 9 класс Мерзляк Задание 694

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\[1)\ a_{n} = n + 4\]

\[a_{1} = 1 + 4 = 5\]

\[a_{2} = 2 + 4 = 6\]

\[a_{3} = 3 + 4 = 7\]

\[a_{4} = 4 + 4 = 8\]

\[2)\ a_{n} = 4n - 3\]

\[a_{1} = 4 - 3 = 1\]

\[a_{2} = 8 - 3 = 5\]

\[a_{3} = 12 - 3 = 9\]

\[a_{4} = 16 - 3 = 13\]

\[3)\ a_{n} = \frac{n}{n² + 1}\]

\[a_{1} = \frac{1}{2}\]

\[a_{2} = \frac{2}{4 + 1} = \frac{2}{5}\]

\[a_{3} = \frac{3}{9 + 1} = \frac{3}{10}\]

\[a_{4} = \frac{4}{16 + 1} = \frac{4}{17}\]

\[4)\ a_{n} = \frac{2^{n}}{n}\]

\[a_{1} = \frac{2}{1} = 2\]

\[a_{2} = \frac{4}{2} = 2\]

\[a_{3} = \frac{8}{3}\]

\[a_{4} = \frac{16}{4} = 4\]