已知数列
、
均为等差数列,且前n项和分别为
和
,若
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c737b1632546c67a2904ca5e2495df28.png)
_____ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e78b6e152498bfa111a95d330a330765.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c737b1632546c67a2904ca5e2495df28.png)
更新时间:2019-10-21 21:42:21
|
相似题推荐
填空题-单空题
|
适中
(0.65)
解题方法
【推荐1】在
中,三边长是公差为2的等差数列,若
是钝角三角形,则其最短边长可以为______________ .(写出一个满足条件的值即可)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
【推荐2】已知实数
成等差数列,点
在直线
上的射影是
,则
的轨迹方程是______________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fe413b12ffabfb252121aa2eaa31017.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50f6e1f67dc15c3cf135a78af95c70fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
【推荐1】等差数列
,
的前
项和分别为
,
,且
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa1f959646f47d0b32bfa6a3411ae55f.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d688603a69081e9ccce3281de42ce70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa1f959646f47d0b32bfa6a3411ae55f.png)
您最近一年使用:0次
填空题-单空题
|
适中
(0.65)
名校
【推荐2】设
和
分别是等差数列
与
的前n项的和,若对任意的
都有
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbb1a1639514ea48c16f96f5774d8e81.png)
_________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3cfeacc29e6a61c5b3b4e439c0a91df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63f5c583c98a1fd516c6ceaa60b55dec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d471926f7b27322d90c82b9ce21d3d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5fce83115a50f99e08e9a2db7267aeed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cea4ac187cbb465180e89f38250b3970.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c9decd300f0dbf7d78fc58ccf3902f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbb1a1639514ea48c16f96f5774d8e81.png)
您最近一年使用:0次