名校
1 . 在通用技术课上,老师给同学们提供了一个如图所示的木质正四棱锥模型
,点E在棱PB上,满足
, 点F在棱PC上,满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5903fee1829219bc74dac66cc9c539d.png)
要求同学们按照以下方案进行切割:
平面
,并说明理由;
(2)过点A,E,F的平面α交PD于点H,沿平面α平将四棱锥模型切割成两部分,在实施过程中为了方便切割,需先在模型中确定H 点的位置;
①请求出
的值;
②若正四棱锥模型
的棱长均为6,求直线
与平面α所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae488b3296fac8508330bc4e3bda5c46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5903fee1829219bc74dac66cc9c539d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c915b4ce31fabfd4703c547291ad9277.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90131175c3fb6a3837a22d7d5bbc268d.png)
(2)过点A,E,F的平面α交PD于点H,沿平面α平将四棱锥模型切割成两部分,在实施过程中为了方便切割,需先在模型中确定H 点的位置;
①请求出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/019c01a933a1844d9a7909e7bcf1b103.png)
②若正四棱锥模型
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
您最近一年使用:0次
2 . 刻画空间的弯曲性是几何研究的重要内容,用曲率刻画空间的弯曲性,规定:多面体顶点的曲率等于2π与多面体在该点的面角之和的差,其中多面体的面的内角叫做多面体的面角,角度用弧度制.例如:正四面体每个顶点均有3个面角,每个面角均为
,故其各个顶点的曲率均为
.如图,在直三棱柱
中,点A的曲率为
,N,M分别为AB,
的中点,且
.
平面
.
(2)证明:平面
平面
.
(3)若
,求二面角
的正切值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba7b2dd83fcacead6b6c7733503dfcee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8e79fd1a2ba4245c902b45bf9fc5c7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c0211da37e92f915e781691296578ba0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/047dc9795efa99b6fb9fdf9778085dab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/00c25c4259d935d6e6fabe5c3fc1f43c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)证明:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf0b52ab4b32b650e57f9233c1b9bd30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6c5282bc1ea20767a6c092c22c761ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f95c6dbe3dde6e5b84a240b2baf87201.png)
您最近一年使用:0次
名校
解题方法
3 . 在直四棱柱
中,底面ABCD为平行四边形,
.![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bfddae02f510917d81779fdc6e74400.png)
(2)若
,当
与平面
所成角的正弦值最大时,求四棱锥
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8094898841f3c4cf83693fecb3f93f2e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccbd1316b9d1f0c1e71fd078deec61f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5bfddae02f510917d81779fdc6e74400.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57bbb335c9028c75c77efa2984ae2171.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
您最近一年使用:0次
名校
4 . 如图,在三棱柱
中,底面是边长为2的等边三角形,
,D,E分别是线段
的中点,
在平面
内的射影为D.
平面
;
(2)若点F为棱
的中点,求三棱锥
的体积;
(3)在线段
上是否存在点G,使二面角
的大小为
,若存在,请求出
的长度,若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/462b1c65b1b233ab98a90c164c0968c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d8485573874c071b1d56e0c1d06d5c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1241216f3c1cb5e73043dd1037f556d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d26d8a9d64ad3c8cba28840b41ed7837.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34be4e71cabf458f17a6cd7f24bc70af.png)
(2)若点F为棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f1f229274a6e17977cc047814212589.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/820a55066be63da11d346175942b09aa.png)
(3)在线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/56f7ba05c54b3de1f4378f7c8eb58328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6460959e79869f0c8cf8613cd211688.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15615de1a6df206dbd081251f676578e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2fec5bd77cfc1313bc200480cc66c766.png)
您最近一年使用:0次
名校
5 . 下列命题正确的是__________ .(填序号)
①若一条直线平行于两个相交平面,则这条直线与这两个平面的交线平行;
②垂直于同一条直线的两直线平行;
③两个平面互相垂直,过一个平面内任意一点作交线的垂线,必垂直与另一个平面;
④过两个点与已知平面的垂直的平面可能不存在;
⑤过两条异面直线外任一点有且只有一条直线与这两条异面直线都垂直;
⑥到一个四面体的四个顶点的距离都相等的平面有7个.
①若一条直线平行于两个相交平面,则这条直线与这两个平面的交线平行;
②垂直于同一条直线的两直线平行;
③两个平面互相垂直,过一个平面内任意一点作交线的垂线,必垂直与另一个平面;
④过两个点与已知平面的垂直的平面可能不存在;
⑤过两条异面直线外任一点有且只有一条直线与这两条异面直线都垂直;
⑥到一个四面体的四个顶点的距离都相等的平面有7个.
您最近一年使用:0次
名校
解题方法
6 . 已知正方体
棱长为2,
为棱
的中点,
为正方体表面上一动点,下列说法中正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
A.点![]() ![]() ![]() ![]() ![]() |
B.点![]() ![]() ![]() ![]() ![]() |
C.当点![]() ![]() ![]() ![]() |
D.若![]() ![]() ![]() |
您最近一年使用:0次
名校
解题方法
7 . 已知点P在棱长为2的正方体
表面运动,且
,则线段AP的长的取值范围是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fee2699b73969f3059a987853a52aa6.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
名校
解题方法
8 . 已知正四棱锥
的所有棱长都为2,点
在侧棱SC上且
,过点
且垂直于SC的平面截该棱锥,得到截面多边形
,则
的边数为__________ ,
的面积为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/faeb97acf19bd3b2c6c77c2814df4d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94a45731695b5b3a1b0ff45dac9b210e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
您最近一年使用:0次
名校
9 . 已知正方体
边长为1,点
分别在线段
和
上,
,动点
在线段
上,且满足
,分别记二面角
,
的平面角为
,则总有( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a7c765f23652ca1f8c3742eaddbe036.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cfbc0b5a8fbde804bd8425a4b76d207.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffd1c59fef41f51963184c0307391299.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a32153ac3499f087eb9099c0346a653.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a079eac0a19273ceb350422b4992f9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be9997e2b3b27407aaa080fd811c8697.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61ba63ad02b1d5af2982fac3d91eb15c.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
您最近一年使用:0次
名校
解题方法
10 . 如图,棱长为2的正方体
的外接球的球心为O,E、F分别为棱AB、
的中点,G在棱BC上,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
A.对于任意点G,![]() |
B.存在点G,使得![]() |
C.直线EF被球O截得的弦长为![]() |
D.过直线EF的平面截球O所得的截面圆面积的最小值为![]() |
您最近一年使用:0次