1 . 如图,正方体
的边长为2,
,
分别为
,
的中点,在五棱锥
中,
为棱
的中点,平面
与棱
,
分别交于
,
.
(1)求证:
;
(2)若
底面
,且
,求直线
与平面
所成角的大小,并求线段
的长.
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/5371d6860fdd4c2985d90e6d66f417e9.png?resizew=51)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/28cd28f95d1a4a8c9e4564a9c46f5494.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/dc1bbe151d8a4cf396fd7140673bc0ac.png?resizew=16)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/2ff003b0353e4b23bf3d9a2ba0d15a00.png?resizew=32)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/3dedf01b2202410ca2978591d0fdcf53.png?resizew=31)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/44bd1b7ce43d47c39fd54f6612882f46.png?resizew=84)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/7e2b053fdd614e27bc9c671105fe04ed.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/f2b9fc222e4b476eafcd71e15162bb5a.png?resizew=25)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/1e7ae17a1f9b4364a9e4d2a490f86ade.png?resizew=37)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/09be45b411f0462cb7dda26fb34062d3.png?resizew=27)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/1d0b9eb5054143c9adb640525fc34672.png?resizew=17)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/e675f5504f424e548dee9d57b7cdbaa9.png?resizew=19)
(1)求证:
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/c11885a458ab4031bf54ba9ae8adefc0.png?resizew=63)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/e1178bc8f1784c53a390fd9400c665ee.png?resizew=59)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66b1a3078dc4803bd5e16833ddd459e0.png)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/fc7d94ecf9e3460182c1f7a229ba29f0.png?resizew=27)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/1e7ae17a1f9b4364a9e4d2a490f86ade.png?resizew=37)
![](https://img.xkw.com/dksih/QBM/2014/6/20/1571782625320960/1571782630924288/STEM/209e36a615a94c669b0e7eb2077439a3.png?resizew=29)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/29/97b7a5a2-ce3f-4f97-a65d-fc423673537e.png?resizew=182)
您最近一年使用:0次
2016-12-03更新
|
4336次组卷
|
2卷引用:2014年全国普通高等学校招生统一考试理科数学(北京卷)
真题
2 . 已知
是等差数列,其前n项和为Sn,
是等比数列,且
,
.
(Ⅰ)求数列
与
的通项公式;
(Ⅱ)记
,
,证明
(
).
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/122e4095de9c438b83b6d8ab15dc8b44.png)
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/a64834c6aa104d5ca2cdc4cafaa6f6b7.png)
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/f96e4c86745e44c1b2354d4071bf7401.png)
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/95dd55929e3c4195b0e4d9f1781373e5.png)
(Ⅰ)求数列
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/122e4095de9c438b83b6d8ab15dc8b44.png)
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/a64834c6aa104d5ca2cdc4cafaa6f6b7.png)
(Ⅱ)记
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/b20dfae231c04fb2b10f83312bf91313.png)
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/c04760633ad54f5a866a340bbfdc7a08.png)
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/262e9911911544759d4a216eb312f7a1.png)
![](https://img.xkw.com/dksih/QBM/2012/7/6/1570917326241792/1570917331623936/STEM/c04760633ad54f5a866a340bbfdc7a08.png)
您最近一年使用:0次
真题
名校
3 . 已知
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5df88d6532c30be1664f1c57fa274b38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/185770a965bb59463b8b938d3ed3a6db.png)
您最近一年使用:0次
2016-12-02更新
|
2615次组卷
|
8卷引用:2013年全国普通高等学校招生统一考试数学(江苏卷)
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