1 . 用反证法证明“若
的三边
、
、
的倒数成等差数列,则
”时,应假设( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c42c44523d227481d31a7de345f904d9.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
解题方法
2 . 如图,已知正四棱台
的侧棱与底面所成的角为
,O为下底面
的中心,
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/5/2296ba12-dde3-4b95-b0dd-620aad55b2c0.png?resizew=285)
(1)证明:
平面
;
(2)求正四棱台
的体积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/be6a6301878fed2a01413020b27310a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d134433600df75f2a5d0f35deb2cac90.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/5/2296ba12-dde3-4b95-b0dd-620aad55b2c0.png?resizew=285)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7de4723157b880c06d8c3d379149316b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11c3590fe4de811edc0723205a081334.png)
(2)求正四棱台
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
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名校
3 . 如图,在平面几何里有射影定理:设
的两边
,
是点
在
边上的射影,则
.拓展到空间,在四面体
中,
平面
,点
是
在平面
内的射影,且在
内,类比平面三角形的射影定理,
,
,
三者面积
,
,
之间有什么关系?请写出你得到的结论,并证明.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/1/ba54e7e1-591c-4075-bbd7-71c6c7a7fbcc.png?resizew=215)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36c4559d27e3905980d1a4f1856f07de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57993f1a74ba00fd159d3939d548557f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/891579e7c231584a8e16b8eeff79888e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd654221ab95fe241d9e0202443f2609.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/661ff55b5ebbadfb600989af3cfce2fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a7ffcd1925a2b1259221c6a476152f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e3a9ec45721f7b4d1c99917ac0d970f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5cbff84327e964f912a54032e76ccc9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3219863e8252a5a006cd216ce9d0352.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d05c329b0a98877e1672af3912633c46.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/1/ba54e7e1-591c-4075-bbd7-71c6c7a7fbcc.png?resizew=215)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/7/1/bb65720d-aab7-4497-b62a-b9107ab6a99b.png?resizew=210)
您最近一年使用:0次
2022-06-30更新
|
71次组卷
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2卷引用:江西省吉安市2021-2022学年高二下学期期末教学质量检测数学(文)试题
4 . 已知
,
,且
,请分别用分析法和综合法证明
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/94440d3e4c073f94f2b266ff99d50e74.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67ca5fd57c2c2fcc3c7a574fdd1467d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5be97cd1c7111b654d87d8fbb63b6a84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4dcc5d823c113fcd61c4b7e9639a5a9.png)
您最近一年使用:0次
名校
解题方法
5 . 在平行四边形
中
过
点作
的垂线交
的延长线于点
,
.连结
交
于点
,如图1,将
沿
折起,使得点
到达点
的位置.如图2.![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
平面![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3cdb19af3fe72be6542fb0d94f285b2.png)
(2)若
为
的中点,
为
的中点,且平面
平面
求点
到平面
的距离.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6ff8798ad33bd2cf83542cedab426dc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/941eba4dbc1094107e1eeb02c8d8cd56.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ccaee8f228ff24e7c89879bb5b999cf2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a25c28359f8d8da9eaf4672a6cf8ae4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1633988fd62a652de726ee92a917b52d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3cdb19af3fe72be6542fb0d94f285b2.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/16b77a5c3865855fbb3d24f9522ced8d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c707f0202ec1aa233e1eeacc7a4587d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e78f6e09cc900502f9113e8a32e19899.png)
您最近一年使用:0次
2022-06-29更新
|
3527次组卷
|
3卷引用:江西省南昌市八一中学2021-2022学年高二下学期期末考试数学(文)试题
江西省南昌市八一中学2021-2022学年高二下学期期末考试数学(文)试题浙江省温州市乐清市知临中学2022-2023学年高一下学期期中数学试题(已下线)核心考点8 立体几何中综合问题 B提升卷 (高一期末考试必考的10大核心考点)
解题方法
6 . 已知数列
满足
,
(
).
(1)求证数列
为等差数列;
(2)设
,求数列
的前
项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b065334d8f60c49f4bd3d9f1373fe4cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/505f0fa805274dec7c2ef6cdf197b152.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/209559aca6bf32705588b6a40e0b7320.png)
(1)求证数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/647020b0a1c11eaa91eb2b4ed9f2dd78.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f730fee4a39e2743a5fb1dc26800354c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
您最近一年使用:0次
2022-06-02更新
|
793次组卷
|
5卷引用:江西省上饶市六校2021-2022学年高二下学期期末联考数学(理)试题
江西省上饶市六校2021-2022学年高二下学期期末联考数学(理)试题湖北省部分重点中学2021-2022学年高二下学期3月联考数学试题(已下线)专题18 等差数列及其求和(讲义)-2023年高考数学一轮复习精讲精练宝典(新高考专用)(已下线)第四章 数列章末重点题型归纳(2)(已下线)模块四 专题2 期末重组练(江西)
名校
解题方法
7 . 已知函数
.
(1)求不等式
的解集;
(2)记函数
的最小值为
,正实数
,
满足
,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ceee492e1b65894c0285de16c054b35a.png)
(1)求不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab989f85a681b41c29465d4be74b789f.png)
(2)记函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab04de6651256f6281e9f4c1dc3c7955.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76dabf2bcd1d88c5a3ffc27619945276.png)
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2022-07-05更新
|
277次组卷
|
3卷引用:江西省抚州市七校2021-2022学年高二下学期期末考试科数学(文)试题
名校
解题方法
8 . 已知
是圆
上的动点,
是线段
上一点,
,且![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad05a28074ade32485ce9e425daa75cf.png)
(1)求点
的轨迹
的方程
(2)过
的直线
分别与轨迹
交于点
和点
,且
,若
分别为
的中点,求证:直线NH过定点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/10596201aaadf88e55ea0809c386cbf0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9d63d61a066b016ab712483c0ad6271.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad05a28074ade32485ce9e425daa75cf.png)
(1)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c45bb20ad47bdf084db4873fa0a198d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44434b647ec546fe787e2164e0be6cd2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91e1e4115d78e625e9e0f47cdade3286.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cf33d73483c93f24cc6a1d76ef22ca6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d571549bbabbdce48c78e5b2cbd964.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0fe46b23cb22ac73fde6c883beb4abad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4914fef4302bc558cbe6bad66de49ad6.png)
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解题方法
9 . 如图,直三棱柱
中,
,
,点E,F,G,H分别是棱
,BC,
,CA的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/2/ce9c0c36-6828-4e44-9719-1712240fbca2.jpg?resizew=177)
(1)求证:
平面
;
(2)求证:
平面BGH.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea6ff6a807f5639faac835012b3728c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/080db3af81b29ed10144a1c2e2a4fb8a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11ddc92d84d188c66b435664a7e7b5a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d88bf46ad08f9677c37eed1d0369329.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/10/2/ce9c0c36-6828-4e44-9719-1712240fbca2.jpg?resizew=177)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/06222ee533c2484ab25321a6abbf98cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ac61c24f99a4e466f1e2ea011893866.png)
(2)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a5f445af1ae136773cb338920552ff2.png)
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10 . 在平面直角坐标系xOy中,以原点O为极点,x轴的非负半轴为极轴建立极坐标系,两点P,Q的极坐标分别为
,以OQ为直径的圆记为⊙C.
(1)求⊙C的直角坐标方程;
(2)若直线l经过点P与⊙C相交于A,B两点,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e36cd93deaad4b58f77a194704470ee.png)
(1)求⊙C的直角坐标方程;
(2)若直线l经过点P与⊙C相交于A,B两点,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a0f1f2f39960424e23b19dcbb0c184a.png)
您最近一年使用:0次
2022-06-30更新
|
165次组卷
|
2卷引用:江西省九江“六校”2021-2022学年高二下学期期末联考数学(文)试题