Question

даю 30 баллов помогите пжпжпжпж

Answer 1

$a_{n + 1} = \frac{81}{a_{n}} \\ a_{1} = 27 \\ a_{2} = \frac{81}{a_{1}} = \frac{81}{27} = 3 \\ a_{3} = \frac{81}{a_{2}} = \frac{81}{3} = 27 \\ a_{4} = \frac{81}{a_{3}} = \frac{81}{27} = 3 \\ a_{5} = \frac{81}{a_{4}} = \frac{81}{3} = 27$