1 . 在三棱锥
中,
平面
,点
是三角形
内的动点(含边界),
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccd4fd4b7a4d6b8ca0c5827c055a9ce7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5426e53bde470d216e49b0b6880cb548.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdb2dd10731b99c0f4f89ee957f8a239.png)
A.![]() ![]() ![]() |
B.三棱锥![]() |
C.![]() ![]() |
D.异面直线![]() ![]() ![]() |
您最近一年使用:0次
2024·全国·模拟预测
2 . 在正三棱锥
中,
,则下列结论正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90a58cd674637680d12e554b5af02cfe.png)
A.异面直线![]() ![]() ![]() |
B.直线![]() ![]() ![]() |
C.二面角![]() ![]() |
D.三棱锥![]() ![]() |
您最近一年使用:0次
2024·全国·模拟预测
3 . 在直三棱柱
中,已知
,
,
为
的中点,点
在
上,若
平面
,则三棱锥
的外接球的表面积为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34c488b33d3d0bbaa79ceaaab9980d48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd19c4db61254be8512edf741bf9f978.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9afac7c616bbb14e1ed428a3c507c7dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec21825261a0433b03cc9d962429496a.png)
您最近一年使用:0次
4 . 如图,已知四边形
是直角梯形,
,
平面
是
的中点,E是
的中点,
的面积为
,四棱锥
的体积为
.
平面
;
(2)若P是线段
上一动点,当二面角
的大小为
时,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34ddc0e6db5f4acd18f4765e05d44bc8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21ec59cea09acc43a8178af846693cdf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06b39b0cfa27b633312db83601cf0359.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6830ebecddbd9759be626289c408e4f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adbd3e8cf8325999cde03adf845d3dd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e5ba482836565abad208665cf7b9972.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6093eebca8f3ff82ce9298feb197e955.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5dd496ee0c1170ef6dcc48266ee444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6895da13331cb525f5850d7b7a02a847.png)
(2)若P是线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b74a85c6a0b3e431dc184d58f957090a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c02b54dc6b3e1bb6544f47d4c8743fcf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/297cc0f9553ef0c5b537c5581eee934c.png)
您最近一年使用:0次
2024·全国·模拟预测
名校
5 . 设数列
的前
项和为
,设甲:
是等比数列;乙:存在常数
,使
是等比数列.已知两个数列的公比都不等于1,则( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.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/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37f4522e22349fd91f76549db8ed9183.png)
A.甲是乙的充分条件但不是必要条件 | B.甲是乙的必要条件但不是充分条件 |
C.甲是乙的充要条件 | D.甲既不是乙的充分条件也不是乙的必要条件 |
您最近一年使用:0次
2024·全国·模拟预测
解题方法
6 . 直三棱柱
中,底面
是以A为直角的腰长为2的等腰直角三角形,侧棱长为
,
为
上的点,若直线
与直线
所成角的余弦值为
,则
长为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d1859959fdb4c5edd8056893f94a10a0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2eb89294b31ffdd2680b4361e8994d7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0467b0675c3ecfb282cc88255284d3e1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
A.1 | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
2024·全国·模拟预测
7 . 如图(1),在
中,
,
,点
为
的中点.将
沿
折起到
的位置,使
,如图(2).
.
(2)在线段
上是否存在点
,使得
?若存在,求二面角
的余弦值;若不存在,说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b757f0c42ae5c9a2d6a4b19e5877b27.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77254996f9c0b31d0cf5a4f01ac46041.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ac451db3443cabb204f96c31fd4a02e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/177678001b2ccde1db8f57fa5e017002.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bffd657e48b15b9b54a55817e2c26b22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a916d31a199e250556fb7478d9f57f7.png)
(2)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9072b0fae4133badde0a221234cca8f4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3507a1f894fac6b554a49b1167965bbb.png)
您最近一年使用:0次
2024·全国·模拟预测
8 . 在平面直角坐标系xOy中,已知圆A:
,点
,点P为圆A上任意一点,线段BP的垂直平分线和半径AP所在直线相交于点Q,当点P在圆上运动时,点Q的轨迹为C.
(1)求C的方程.
(2)斜率存在且不为0的直线l与C交于M,N两点,点D在C上.从下面①②③中任选两个作为已知条件,证明另外一个成立.
①
轴;②直线l经过点
;③D,B,N三点共线.
注:若选择不同的组合分别解答,则按第一个解答计分.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/550d183b05000722c74baf25eb4a6741.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2c77a42750684cb6157c2c7fb9422a3.png)
(1)求C的方程.
(2)斜率存在且不为0的直线l与C交于M,N两点,点D在C上.从下面①②③中任选两个作为已知条件,证明另外一个成立.
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4914b846a985658a528ab9d70ccc7c30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f28491f7ef64389d62b0e1574ab56429.png)
注:若选择不同的组合分别解答,则按第一个解答计分.
您最近一年使用:0次
2024·全国·模拟预测
名校
解题方法
9 . 已知O为坐标原点A,B,C为椭圆E:
上三点,且
,
,直线BC与x轴交于点D,若
,则E的离心率为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dd54b9df3402ad91e2d34c40efe0c7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaef66ff7c6aaaad19133c1177bb564.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f8e382a7ddf35397c2b5e722b345b507.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5640b18cf5f9aaa9e6b35d03b7c33d4e.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次