名校
解题方法
1 . 魏晋时期数学家刘徽(图a)为研究球体的体积公式,创造了一个独特的立体图形“牟合方盖”,它由完全相同的四个曲面构成,相对的两个曲面在同一圆柱的侧面上.如图,将两个底面半径为1的圆柱分别从纵横两个方向嵌入棱长为2的正方体时(如图b),两圆柱公共部分形成的几何体(如图c)即得一个“牟合方盖”,图d是该“牟合方盖”的直观图(图中标出的各点
,
,
,
,
,
均在原正方体的表面上).
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/b76aa339-7164-4091-a34b-d8688623f5cf.png?resizew=766)
(1)由“牟合方盖”产生的过程可知,图d中的曲线
为一个椭圆,求此椭圆的离心率;
(2)如图c,点
在椭圆弧
上,且三棱锥
的体积为
,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acc290b44635265137fdf13146b6a6d9.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/10/b76aa339-7164-4091-a34b-d8688623f5cf.png?resizew=766)
(1)由“牟合方盖”产生的过程可知,图d中的曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f42d53a48595e6f0be79d75a12938e89.png)
(2)如图c,点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96cf01ce6c1bf3a909feaee502aebcc2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4dac452fbb5ef6dd653e7fbbef639484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ead4139ed996caf2ab621c53cfde772d.png)
您最近一年使用:0次
名校
解题方法
2 . 已知如图甲所示,直角三角形SAB中,
,
,C,D分别为SB,SA的中点,现在将
沿着CD进行翻折,使得翻折后S点在底面ABCD的投影H在线段BC上,且SC与平面ABCD所成角为
,M为折叠后SA的中点,如图乙所示.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/1/bed5ceea-5766-4ecb-a1e1-8eb6b5000cd5.png?resizew=345)
(1)证明:
平面SBC;
(2)求平面ADS与平面SBC所成锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/148649805098fe3c70919f18dceb5a11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4df5ee7d6f1a6eb46d93cb274e9fcac9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c009f663ad2b0c3ba521daf4b86b066f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d88591679796c52024d11c4de641bdb.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/4/1/bed5ceea-5766-4ecb-a1e1-8eb6b5000cd5.png?resizew=345)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ba8f7af0e091e082100c3cd7f8c487f.png)
(2)求平面ADS与平面SBC所成锐二面角的余弦值.
您最近一年使用:0次
2023-03-31更新
|
1365次组卷
|
4卷引用:重庆市巴蜀中学2023届高三下学期高考适应性月考(八)数学试题
重庆市巴蜀中学2023届高三下学期高考适应性月考(八)数学试题海南省琼海市嘉积中学2022-2023学年高二下学期5月期中数学试题江西省铜鼓中学2022-2023学年高二下学期4月月考数学试题(已下线)重难点突破06 立体几何解答题最全归纳总结(九大题型)-1
名校
3 . 如图,在圆台
中,
分别为上、下底面直径,且
,
,
为异于
的一条母线.
为
的中点,证明:
平面
;
(2)若
,求二面角
的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/192f4f9446c954a291f779d963f90257.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/601050d23e9d0b81ee6c5eda991dbdf9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86605a29fe8fff454e0db6b86047a8fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/439cf259dd6137aa31bb99244a04ddfc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c95c0160e73beb94a4a1cbc0168e9a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/afabf56cc68ea438a890f9fea04b708e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebc9e0457471047bc750ecd31989414a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6647d7d03d64dc6eac2c9651badd9376.png)
您最近一年使用:0次
2023-03-29更新
|
5583次组卷
|
14卷引用:重庆市缙云教育联盟2023届高三二模数学试题
重庆市缙云教育联盟2023届高三二模数学试题江苏省八市(南通、泰州、扬州、徐州、淮安、连云港、宿迁、盐城)2023届高三二模数学试题(已下线)专题07立体几何的向量方法(已下线)押新高考第20题 立体几何(已下线)江苏省八市2023届高三二模数学试题变式题17-22专题16空间向量与立体几何(解答题)江苏省部分四星级高中2023-2024学年高三上学期期初调研数学试题(已下线)江苏省南通市如皋市2023-2024学年高三上学期期初调研数学试题广东省湛江市第一中学2023-2024学年高二上学期第一次大考数学试题江苏省八市2023届高三下学期第二次调研测试数学试题江苏省镇江市扬中市第二高级中学2023-2024学年高三上学期期末模拟数学试题3(已下线)空间向量与立体几何江苏省南京外国语学校2023-2024学年高三上学期期中模拟数学试题2024届安徽省阜阳市皖江名校联盟高三模拟预测数学试题
解题方法
4 . 在几何体
中,底面
是边长为6的正方形,
,
,
,
均为正三角形,且它们所在的平面都与平面
垂直.
是线段
上的动点,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/4/12e03020-2ad4-4276-97df-0cb1f1bf54cf.png?resizew=155)
(1)若
,求三棱锥
的体积;
(2)若平面
平面
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d17d4a6cf11cda87b3dfafaecdec683f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f14b86b8bf99386fc939c9c12b1355ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6a0c85deb80d8e63bc60127e803f7ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7ab8de2231d3bfbd289dcdf6d512667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6801e866d3f9f26886e271708a73a6b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0e57a13c665af88f326c9890072bf73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2e6648c9e56d68506017df7424be99c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/4/12e03020-2ad4-4276-97df-0cb1f1bf54cf.png?resizew=155)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1c3ea872a20fdc1843cb5ffce8a554.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1234a7bbfe925eeea7f17d30bfab88b3.png)
(2)若平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8cbfb8a8a4d0731f5b237d5c8e169725.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24fac8b38a9cf7602391f6d6ca933bd2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
您最近一年使用:0次
2022-12-04更新
|
474次组卷
|
4卷引用:重庆市綦江区等5地2023届高三上学期12月月考数学试题
名校
5 . 如图,
,O分别是圆台上、下底的圆心,AB为圆O的直径,以OB为直径在底面内作圆E,C为圆O的直径AB所对弧的中点,连接BC交圆E于点D,
,
,
为圆台的母线,
.
![](https://img.xkw.com/dksih/QBM/2022/6/2/2992878723137536/2995463831691264/STEM/67c8a0f1-0048-44a8-922a-3e5c732087a7.png?resizew=275)
(1)证明;
平面
;
(2)若二面角
为
,求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2777840758e70e7dbbc18cef8f3d6d2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0a851907ada2ac2c3c4880a6736d28a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc47e8015e70a20456c25f742d54cae.png)
![](https://img.xkw.com/dksih/QBM/2022/6/2/2992878723137536/2995463831691264/STEM/67c8a0f1-0048-44a8-922a-3e5c732087a7.png?resizew=275)
(1)证明;
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/92bced6bf70db7229db85f2b10339431.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96561270cf8ba626c335de419a348774.png)
(2)若二面角
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6b3b3c5608839553d9b08be66be43c8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d88591679796c52024d11c4de641bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c2e528bb8fc7c95fec7ecc510d04034.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41104641f3e2260d00aeadf8fb8a078a.png)
您最近一年使用:0次
2022-06-06更新
|
1314次组卷
|
5卷引用:重庆市缙云教育联盟2023届高三上学期9月月度质量检测数学试题
名校
解题方法
6 . 已知四棱锥
中,底面
为正方形,O为其中心,点E为侧棱
的中点.
![](https://img.xkw.com/dksih/QBM/2022/3/16/2937213962313728/2938940206055424/STEM/0d4305f72296407892f1aa3ea1be8bf9.png?resizew=228)
(1)作出过O、P两点且与
平行的四棱锥截面(在答题卡上作出该截面与四棱锥表面的交线,并写出简要作图过程);记该截面与棱
的交点为M,求出比值
(直接写出答案);
(2)若四棱锥的侧棱与底面边长均相等,求
与平面
所成角的正弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://img.xkw.com/dksih/QBM/2022/3/16/2937213962313728/2938940206055424/STEM/0d4305f72296407892f1aa3ea1be8bf9.png?resizew=228)
(1)作出过O、P两点且与
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c21e3e66b01ebf71bb68cf88f6c1155.png)
(2)若四棱锥的侧棱与底面边长均相等,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
您最近一年使用:0次
名校
7 . 如图,在圆锥
中,
为底面圆的直径,
为底面圆上两点,且四边形
为平行四边形,过点
作
,点
为线段
上一点,且满足
.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/c8bcd9c6-b9f8-44f4-87b6-5fc45c4d0d57.png?resizew=174)
(1)证明:
平面
;
(2)若圆锥
的侧面积为底面积的2倍,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/270ddac9587bf1ea553914cb69595ab2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/39acab3cfb59bfc9591371721ab01d93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba00756582afde4e4e75f4a2b189295b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12fe32dfbd66709875c5b9f79c9496da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/451557ef624a9c142ebc5fa155e0e28b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b90e0f35eda1a729fed485f83da5ea9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae6c4037c6d20d251e94dc2730b0dad1.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/2/c8bcd9c6-b9f8-44f4-87b6-5fc45c4d0d57.png?resizew=174)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97f30533da2e1d2a958dc906c37eba9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a77343ecde1c2665df291761b6563.png)
(2)若圆锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/270ddac9587bf1ea553914cb69595ab2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15774872dbe4d9f2c16b997299451f46.png)
您最近一年使用:0次
2022-02-09更新
|
1294次组卷
|
4卷引用:重庆市第八中学2022届高三下学期调研检测(三)数学试题
名校
8 . 三棱锥
中,
,
,
,直线
与平面
所成的角为
,点
在线段
上.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/1401ce1c-58c3-4119-8bb6-4cd452cd97c2.png?resizew=160)
(1)求证:
;
(2)若点
在
上,满足
,点
满足
,求实数
使得二面角
的余弦值为
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63397cda22cb1fad59cf966dfb588643.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/463c7753d6f7614f90b19245bb3e439e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1affed1ad8e53a73308c85849a72444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4cbb05b8b630052ff544249ebd72d95d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d88591679796c52024d11c4de641bdb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd33764ff4efddfe11a98a609753715c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/12/28/1401ce1c-58c3-4119-8bb6-4cd452cd97c2.png?resizew=160)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/70734a8e672376bb0bd1522e229f86a2.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4bb04187b181054c7ddc7f0e35e3e5d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c49e8906f0de208b36a18e448f7ecc7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/445b51117626fbd3373e32acc514c64b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d33adb74906403b0b00fcbd9fa691d8b.png)
您最近一年使用:0次
2022-01-21更新
|
667次组卷
|
4卷引用:重庆市巴蜀中学2021-2022学年高二上学期期末数学试题
名校
解题方法
9 . 如图1,在
中,
,过点A作
,垂足
在线段
上,沿
将
折起,使
(图2),点
分别为棱
的中点.
![](https://img.xkw.com/dksih/QBM/2022/2/16/2917867928952832/2921885495640064/STEM/8999d854b863426f94ab6e0e44986f33.png?resizew=442)
(1)求证:
;
(2)已知_____(在后面三个条件中任选一个,补充在横线上),试在棱
上确定一点
,使得
,并求二面角
的余弦值(如果选择多个条件分别解答,按第一个解答计分).
条件①:图1中
;
条件②:图1中
;
条件③:图2中三棱锥
的体积为
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f94efa5055d28df98174c70468f691e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b5f215a42c4b7078d8d65923eb9980e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.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/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/587458141d890533c0c32aa249a27ad0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e9ea567f329fd06508903a815f71561.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/887721a843b2dc8e947cc42d09868e33.png)
![](https://img.xkw.com/dksih/QBM/2022/2/16/2917867928952832/2921885495640064/STEM/8999d854b863426f94ab6e0e44986f33.png?resizew=442)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73038c8fab9ef31d42b3ee0631b3dd1c.png)
(2)已知_____(在后面三个条件中任选一个,补充在横线上),试在棱
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5448218bd8c5b4f4a3714e0b0292d2f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4f8bee68df4d2f8bdcd86cde8b91450.png)
条件①:图1中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/30a050eb958818c6b6de98640c943df1.png)
条件②:图1中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ae053beafc8a7007f6127407d6ce6fd.png)
条件③:图2中三棱锥
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
您最近一年使用:0次
2022-02-22更新
|
592次组卷
|
3卷引用:重庆市暨华中学校2021-2022学年高二上学期10月月考数学试题
重庆市暨华中学校2021-2022学年高二上学期10月月考数学试题四川师范大学附属中学2022届高三二诊二模考试理科数学试题(已下线)第四章 立体几何解题通法 专题二 升维法 微点3 升维法综合训练【培优版】
10 . 如图,已知圆柱的上,下底面圆心分别为
是圆柱的轴截面,正方形ABCD内接于下底面圆Q,
.
![](https://img.xkw.com/dksih/QBM/2021/12/21/2877184706306048/2916904990130176/STEM/69f5bc23f7314f5c8dabf6d4b54890aa.png?resizew=126)
(1)当k为何值时,点Q在平面PBC内的射影恰好是△PBC的重心;
(2)若
,当平面PAD与平面PBC所成的锐二面角最大时,求该锐二面角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f54840995c545df777ab9196813ddc5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/667206277277c8a79bd370cb167a6acd.png)
![](https://img.xkw.com/dksih/QBM/2021/12/21/2877184706306048/2916904990130176/STEM/69f5bc23f7314f5c8dabf6d4b54890aa.png?resizew=126)
(1)当k为何值时,点Q在平面PBC内的射影恰好是△PBC的重心;
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0ad013ed89855a7f3c795c48bc7c91f1.png)
您最近一年使用:0次
2022-02-15更新
|
1304次组卷
|
2卷引用:重庆市璧山来凤中学校九校2023届高三上学期联考模拟(二)数学试题