等差数列{a n }中,a 1 =84,a 2 =80,则使a n ≥0且a n+1 <0的n为( )
A.
21
B.
22
C.
23
D.
24
手机使用
分享
复制链接
新浪微博
分享QQ
微信扫一扫
微信内点击右上角“…”即可分享
反馈
参考答案:
举一反三
【简答题】Experts say that
being appropriately dressed is essential for good impressions, so attach
great importance to your attire while you are in the office.
【简答题】阅读理解。 Do you want to live another 100 years or more? Some experts say that scientific advances will one day enable humans to last tens of years beyond what is now seen as the natural limit of the huma...
【简答题】阅读理解 Do you want to live another 100 years or more? Some experts say that scientific advances will one day enable humans to last tens of years beyond what is now seen as the natural limit of the human...