数学试题讲解

已知数列

{a_{n}}

满足

\frac{a_{n + 1} - a_{n}}{(1 + a_{1}^{2}) (1 + a_{2}^{2}) . . . (1 + a_{n}^{2})} = 0 (n \in N^{*})

, 则

a_{2021} > a_{1}

a_{2021} < a_{1}

C. 数列

{a_{n}}

是等差数列 D. 数列

{a_{n}}

是等比数列