1 . 设
,
,正实数数列
满足
,且当
时
.求证: ⑴当
时,
; ⑵
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1465145d6bc8543d5c544dd99613970d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08115d6d9f876dea921a4d32260ff1fb.png)
![](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/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27008dcb6262187804a14cab9302a876.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c10652cbb829968425b5d43b3e19eea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a347b7b06cf3541256a952adfe637750.png)
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2 . 如图,
、
是双曲线
的两个焦点,一条直线与双曲线的右支相切,且分别交两条渐近线于A、B.又设O为坐标原点,求证: (1)
; ⑵
、
、A、B四点在同一个圆上.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/565bc68d208cd5e0c90a32851faf3814.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a05d4d803a85dc1059912895954551b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f5076289823db419f94e9c0c8f4aafd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a3fb78c5f885034612c0e030b920143d.png)
![](https://img.xkw.com/dksih/QBM/2019/1/28/2128340345315328/2129028866695168/STEM/cd48519e-7460-4653-91b5-2403e14064a5.png)
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2011高三·天津·竞赛
3 . 设
、
、
、
、
、
为实数,且
对任意的实数
成立.证明:
![](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/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/168b3e4b1d6f04226fa2687a72a268b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca4ff0af96ea467337cb30c4c765b5f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/74dcc8b824bf93f5981bfd1fd3d1a71d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9723d411b2a0409c768eb8bbbe2f0bc0.png)
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2013高三·天津·竞赛
4 . 在平面直角坐标系中,设
、
、
是曲线
上的三个不同点,
、
、
分别为边
、
、
的中点.证明:
的外接圆经过原点
.
![](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/377a2333ff8c63cbdb20b882d6d5a7ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9abaeba15f3abdd877bc701af52c5cd9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72cb97395ebc5ee1b212afb7a97b985c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
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2007高三·天津·竞赛
5 . 已知
的外心为
,
,
为
的外接圆上且在
内部的任意一点,以
为直径的圆分别与
交于点
,
分别与
或其延长线交于点
.求证:
三点共线.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37ee7149bd58649b5c8b84439e118e53.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebcc52a06d806fde891e09a0a389fcd4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0d54431bbb28ebd98db5c1dc6083a75.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3a51949f48ee8cf746851ba779b078e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c862ba8f2917907e2924aeb9736b3ad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ace5e8c3769ad8f370c86f879246c174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c741cf8348e9fa4ee6894ac2c3ac6dad.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf3c7ba0963b2c01c7e886442bcceac9.png)
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2011高三·天津·竞赛
6 . 在四面体
中.
面
,
已知
是
上一点,满足
,且
(1)证明:
;
(2)若点
到平面
的距离为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca5dd496ee0c1170ef6dcc48266ee444.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca67a5b8f69507c8b80379e86f90a8ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e56c40061164aae019cafc50d81d5a5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a45b04cc3e5adaeff6f9e01e29032803.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24ff2ae94edbd6437b10463ab52a4f39.png)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d0ed15020c1c669e06a3a3b1557242e9.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6faa377b82f7c39f03875874b78f922b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aefd06c239145a2b6ae87a955aa51414.png)
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7 . 已知有理数数列![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
满足
,其中,
、
,
、
,且
.
证明:(1)
位有理数;
(2)若
、
不是实数,则
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f3c8148f29fa35589392abe05ceb835.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb5a3dcf69a81f8945c6a58d0e1f61d2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/461af8f960bc02af4ee7f438cd9936c4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba2314283c849af7e66dbb1d269e962f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31d900314efb0e4cacb6e5de945b5397.png)
证明:(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/450398974b1561ca801e102e16df6789.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec19b68e3add9d5bfcc6269a1855b87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffa3205b1df826d63914dcb55bb3ab43.png)
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8 . 设
.证明:对任意的
,有
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28d73a960601c6c230915916f77fa12f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/098cadc08395d87ca241558e02933f73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66c860cd97f429172640e48cff703a37.png)
您最近一年使用:0次
9 . 如图,设
的外心、内心分别为
、
,
、
、
内的旁心分别为
、
、
. 证明:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/fbaf18cb-0a76-496a-b1f8-7795a14bf385.png?resizew=182)
(1)
为锐角三角形;
(2)若
的外心为
,则
、
、
三点共线.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e105760638b22b26ff8bec4354255e4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3818a2c9919d358b4c3713396093822b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/febc9a89d0d1c97b88c0f4acd32b4e67.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/194741f4d2ae7ee44cafca780361446a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f1ac49b4139636fb1809fe970b23a87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2d1a0fd1ad044a9ecfcba672779bd678.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f904e5f274c559bdba741df035ed3461.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/1/5/fbaf18cb-0a76-496a-b1f8-7795a14bf385.png?resizew=182)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b341ab9bd1c7472a4ba15dc4cde452ea.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b341ab9bd1c7472a4ba15dc4cde452ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12fe32dfbd66709875c5b9f79c9496da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12fe32dfbd66709875c5b9f79c9496da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e105760638b22b26ff8bec4354255e4c.png)
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