配套习题- 数列通项公式的求法（一） -【青果学院】

1/3单选题

难度：

1.数列-3，1，5，9，…的一个通项公式为（　　）

A	4n-7
B	1-4n
C	n²-4n
D	n-4

正确答案：QQ==

6Kej77ya5pWw5YiXLTPvvIwx77yMNe+8jDnvvIzigKbmmK/pppbpobnkuLotM++8jOWFrOW3ruS4ujTnmoTnrYnlt67mlbDliJc8YnI+4oi0YTxzdWI+bjwvc3ViPj00bi03PGJyPuaVhemAiUEuIA==

2/3单选题

难度：

2.数列7，77，777，7777…的一个通项公式是a_n=()

A
B
C
D

正确答案：Qg==

6Kej77ya5YWI5YaZ5Ye6Oe+8jDk577yMOTk577yMOTk5OeeahOmAmumhueaYrzEwPHN1cD5uPC9zdXA+LTHvvIw8YnI+4oi05pWw5YiXN++8jDc377yMNzc377yMNzc3N+KApueahOS4gOS4qumAmumhueWFrOW8jzxpbWcgd2lkdGg9NjggaGVpZ2h0PTQ1IHNyYz0iaHR0cHM6Ly9wMS5xaW5nZ3VvLmNvbS9HMS9NMDAvRkUvQTMvckJBQ0UxTlF4aml5S2k3REFBQUNzWldndVlBNDg5LnBuZyI+PGJyPuaVheetlOahiOS4uu+8mkI=

3/3单选题

难度：

3.无穷数列1，3，6，10…的通项公式为（　　）

A	a_n=n²-n+1
B	a_n=n²+n-1
C
D

正确答案：Qw==

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