名校
1 . 如下图,四棱锥
的体积为
,底面
为等腰梯形,
,
,
,
,
,
是垂足,平面
平面
.
;
(2)若
,
分别为
,
的中点,求二面角
的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0585b6c0f156eecf9662b9846d4eb693.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf31876698721a199c7c53c6b320aa86.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d5acb763021bf166ca719d07223591d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/279e119eed905cf15026649a1b86502a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a398397362a18da1cc9f24bf3f356ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f29c3e772e56008790298824122792.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7713c13736076f1fe2c139bb4a4b6d6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/93edc7bb513f40a89173121c8570cd65.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9104a1941e557a85fd1496bc2b9be297.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a5d7d3b6b63fe5c24c3907b7a8eaa3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0629ce42392a7fe9be21d25c39c3e64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99ab98efd2b5fcbfeae61fe37f921a0e.png)
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2 . 如图,在三棱锥
中,
平面
分别为棱PC,PB的中点.
平面
;
(2)若
,求二面角
的大小.
![](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/517f89f30121be4d53d6aee05fccf044.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9a32bd7a1b78b5a0ec562c4025aea8c.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/587df01a98f499a9f361aafd8c3dac39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5617a404c5a3356753136e5a6b6d51e5.png)
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3 . 如图,在三棱锥
中,已知
,
,
,
,
,
.
为
的中点,求证:
;
(2)求平面
与平面
夹角的余弦值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/41e5db1d2fd912f77923e4c120a7dc19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080ca48cd27d4bf9d9ef084b558fc17a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef0402dd5ae3db10281f9f1e11738bcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ce64044898d0460aac161d93a455304.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba8c340f8945083d2993ff28eabfcccf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4d6b27a35a18492e60b5b99789d3395.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45acdbac251ca6b76a166c1242e71df9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c177e06cc3f703e8ca7be7c491fa2942.png)
(2)求平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2cc6f6dfdbe7d39891c35f67e1a95c7f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21665d21bbfb04410c78345de1fd15ae.png)
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名校
解题方法
4 . 诚信是立身之本,道德之基.某校学生会创设了“诚信水站”,既便于学生用水,又推进诚信教育,并用“
”表示每周“水站诚信度”.为了便于数据分析,以四周为一个周期,下表为该水站连续八周(共两个周期)的诚信度数据统计,如表1:
(1)计算表中八周水站诚信度的平均数
;
(2)从表中诚信度超过
的数据中,随机抽取2个,求至少有1个数据出现在第二个周期的概率;
(3)学生会认为水站诚信度在第二个周期中的后两周出现了滑落,为此学生会举行了“以诚信为本”主题教育活动,并得到活动之后一个周期的水站诚信度数据,如表2:
请根据提供的数据,判断该主题教育活动是否有效,并根据已有数据说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bc891e44ebe17a1ffc956667a4112bf4.png)
第一周 | 第二周 | 第三周 | 第四周 | |
第一个周期 | ||||
第二个周期 |
(1)计算表中八周水站诚信度的平均数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bfbe7f95b5d89f9409ec24536da9e826.png)
(2)从表中诚信度超过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4426df5be4e96b6385de735db9f69772.png)
(3)学生会认为水站诚信度在第二个周期中的后两周出现了滑落,为此学生会举行了“以诚信为本”主题教育活动,并得到活动之后一个周期的水站诚信度数据,如表2:
第一周 | 第二周 | 第三周 | 第四周 | |
第三个周期 |
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名校
解题方法
5 . 已知
和
都是直角三角形,
,E,F分别是边AB,AD的中点,现将
沿BD边折起到
的位置,如图所示,使平面
平面BCD.
平面BCD;
(2)求证:平面
平面
;
(3)请你判断,
与BD是否有可能垂直,做出判断并写明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661ff55b5ebbadfb600989af3cfce2fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5ff103699fefbd87327b26b58fafd42.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab2a2834d80ff574e79eae8ca8d4e94f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07c967c9b3f669ea78edd838e1d8b59e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba0fbd88fdb064072eedd136e9cb41ff.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57f9d682e5d3cc8573574d8d11636758.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/21dee56b9f36ba8f76fe67b76383636b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74bca84ad86c648d3bb20c8909c8da3f.png)
(3)请你判断,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ee8456443402a25b1e25d35ff7e1c98.png)
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6 . 已知函数
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a57996290794e082b21d8f1dfc322a.png)
(1)如果点
是角
终边上一点,求
的值;
(2)设
,求
的单调递增区间.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9688a68bd2d1b2c8dcd6568e1a5ac3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a57996290794e082b21d8f1dfc322a.png)
(1)如果点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58e7c6b1e8d06e439c1ede19f99286c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/794f2c6bd63355105d179d11306a9cae.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72f3b2cc4fc44eef6a51e1a4ae89ecb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4669810732b633b60dbeaf0bf57204f6.png)
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7 . 如图,点
均在
轴的正半轴上,
,
,…,
分别是以
为边长的等边三角形,且顶点
均在函数
的图象上.
个等边三角形的边长
;
(2)设数列
的前
项和为
,求
.
(3)已知数列
的通项
,数列
中,
,
,求
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ce1e808127c5672eb1b47024e54c9cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/beb99c20237aca8ff2ba640c28fbc5b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a619e2751f422ae187505e95339d02fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b80801bd92f36541707eea1229685e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/699bdb06cc1a8e431fd96fdd06f6d2f3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/43a6e162176d244084d154bc50b598eb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aef469c7b7cb9945b984222381b9c000.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/96abfe2da27a63e6affb19a0c80236d9.png)
(2)设数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d876a9e0ab9abc3880410cfde910eb6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c6ef48976a52cc4a2be7c46a98426c0a.png)
(3)已知数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/267c99ff3f6386113dbaa7b1e49612da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50e1ee88beaddafb0d0a185c3a8e0dc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a655f0f5afe3673c421af8a677b5154c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8427946085d576e0696e06cf4463c30f.png)
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8 . 已知数列
为等比数列,
为等差数列,且
,
,
.
(1)求
,
的通项公式;
(2)若
,数列
的前n项和
;
①求数列
的前n项和
;
②对任意的
,不等式
恒成立,求实数
的取值范围.
![](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/85444874c705666de9488286d3d61dd1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d81f0ceacc025999ece67fb1bc2d452e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdf76ee8248d9d3435f52fd0a9fa73cb.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9221c0c92a526f65533cdc5400767af.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
①求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
②对任意的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e97769855336d73371930df1f187875e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ec1604a0743ed62d833577fd9929c376.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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9 . 为了估计一批产品的质量状况,现对100个产品的相关数据进行综合评分(满分100分),并制成如图所示的频率分布直方图.记综合评分为80分及以上的产品为一等品.
(2)用样本估计总体,以频率作为概率,按分层随机抽样的思想,先在该条生产线中随机抽取5个产品,再从这5个产品中随机抽取2个产品记录有关数据,求这2个产品中最多有1个一等品的概率;
(3)已知落在
的平均综合评分是54,方差是3,落在
的平均综合评分为63,方差是3,求落在
的总平均综合评分
和总方差
.
(2)用样本估计总体,以频率作为概率,按分层随机抽样的思想,先在该条生产线中随机抽取5个产品,再从这5个产品中随机抽取2个产品记录有关数据,求这2个产品中最多有1个一等品的概率;
(3)已知落在
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/486c7705dbd7b7b9ec5dd17b4891088b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea146d8ec45e63ad14683fd31064de66.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1060d57931930bf800beaeaf5e8c18e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d41042207515dd2e8349c805e6aee400.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/671f43c79d612c93a6d160335e86e177.png)
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10 . 如图,在四棱锥
中,四边形
是梯形,
,
,
是等边三角形,
,点
是棱
的中点.
与平面
的交线为
,求证:
;
(2)求证:平面
平面
.
![](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/ae1e04eeb4de72e5750dae77bcb6f88a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1134c8e3440abb6cd385af2c169037fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/55a675310c8ba418e5a59beb7317e21e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/123bf0d9dc2e5237d63a09402da78dee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.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/852aabd89edffc1b94344ff3f1f31ccd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72ee6c7e0dfe134561f818cb51eebe09.png)
(2)求证:平面
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35c9529795ba241d68e1c4ce912b4334.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e582d73b96ba649378379c3074d506d.png)
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