解题方法
1 . 法国著名军事家拿破仑
波拿巴最早提出的一个几何定理:“以任意三角形的三条边为边向外构造三个等边三角形,则这三个三角形的外接圆圆心恰为另一个等边三角形的顶点”.如图,在
中,内角
,
,
的对边分别为
,
,
,已知
.以
,
,
为边向外作三个等边三角形,其外接圆圆心依次为
,
,
.
;
(2)若
的面积为
,求
的面积的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c97ec04a1aa7ac6fce72d589864940a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](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/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/5f83f04929a0b205b78e2d87b7079ecd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/23f919bd3dde10dbbc076f7ec5149699.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c4f6f74444b2b7947fc6e35c8d62322.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dacb04fa29178c0af4353e4369a7e69.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7736a0467e1127dc3963098e148ca64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18483c9c195ecd922772527fa85c0fcb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
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解题方法
2 . 直四棱柱
的所有棱长都为
,
,点
在四边形
及其内部运动,且满足
,则点
到平面
的距离的最小值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6e09725691ee7851f54c0dee86b2bf55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bbaccd578a43b2397c8bdd50592fa07.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2bf9ef324f1289e205e29fed105c38e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f88e265ee000aed605e9fdf328745930.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15b78c047642924fe864028c81b1f49d.png)
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3 . 已知
,向量
,且满足![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcb6a037ca43e342496f5b00870a8689.png)
(1)求点
的坐标;
(2)若点
在直线
(
为坐标原点)上运动,当
取最小值时,求点
的坐标.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baba5942e11975cd2383393d7e619136.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7199e5758b135764a980570891013940.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dcb6a037ca43e342496f5b00870a8689.png)
(1)求点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)若点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef4113c492885ba7c47fe42ac792578f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7787dfab61ed9830b531da365e592bbd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
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解题方法
4 . 在直角三角形
中,
,点
在边
上,且
,设
.
(1)若
,求
的值;
(2)若
,求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8652515789d01ab3af8c9986cf94274a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad056c25c0fdcbcc765eb5cbc6093f2b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/379556ae8865fdf6430f71be2a99f71e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bf718980f931b3f21a332916404fef2f.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/759b29a7b2b3735306f1a650355a7858.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4ee25a78681febe00db64902902420ea.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65397f11ea8af736f38debadf420c4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da336bc7d2112ecff7d1e632ea2df748.png)
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解题方法
5 . 阅读下面材料:在空间直角坐标系
中,过点
且一个法向量为
的平面
的方程为
,过点
且方向向量为
的直线
的方程为
.根据上述材料,解决下面问题:已知平面
的方程为
,直线
是两个平面
与
的交线,则直线
与平面
所成角的正弦值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a834024400d0730af3e640ca4d5f54b4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baf95be25d34a7366bf4060d081329c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1570746ca504965aa6f176e46a0c2760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b523a8c1993478f6599680dc3b3dc45b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/baf95be25d34a7366bf4060d081329c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/392440bbbea2ec683d8f1786370407ec.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/452af21e95f71dc626c04fafafd8ca49.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/975d88a135a66a0ee0fb6b13f6b87b9b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e23fc11a3a7592c68b20f93bdde2ed3f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c001d43d68ea1cd6461c73ee48b1b4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
6 . 在
中,点
是线段
上一点,点
是线段
上一点,且
,
,则
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e44dda388cb29c74ababb811aab2fbc4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2dd85a0f2ff80c84bf23eb808a349320.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5085e3cdef9ea6c564e079f745d6fdb.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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7 . 设
为
的内角,向量
,向量
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf6fa747c6f517302ce91c8e7a846fd8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98317e669d2483e4898c2e171a8106d4.png)
A.对任意![]() | B.存在![]() ![]() |
C.存在![]() ![]() | D.对任意![]() ![]() |
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8 . 在
的展开式中,把
,
,
,…,
叫做三项式的
次系数列.
(1)求
的值;
(2)将一个量用两种方法分别算一次,由结果相同得到等式,这是一种非常有用的思想方法,叫做“算两次”.对此,我们并不陌生,如列方程时就要从不同的侧面列出表示同一个量的代数式,几何中常用的等积法也是“算两次”的典范.根据二项式定理,将等式
的两边分别展开可得左右两边的系数对应相等,如考察左右两边展开式中
的系数可得
.利用上述思想方法,请计算
的值(可用组合数作答).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aa1c8db5d9615fcd93f27c51f2cebbe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4e7de8b609e254729c979ed2d78de9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a80af4d1f81cd067cf2d6a96f314479c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90e4bded23ed1500d9368d6cb117149e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50738c74cc3b9a0f7739ee511803dbd6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cca593eda84c841a7172cd7e4bf4e90b.png)
(2)将一个量用两种方法分别算一次,由结果相同得到等式,这是一种非常有用的思想方法,叫做“算两次”.对此,我们并不陌生,如列方程时就要从不同的侧面列出表示同一个量的代数式,几何中常用的等积法也是“算两次”的典范.根据二项式定理,将等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b624491c6cb586836d591bf8fa3fce70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4e26f2235031a8d214d82a5e405db676.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/65383aa7a73843bd22eac3dc3262dbbb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15ac6d04e7725a6d18d36052fc772b14.png)
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9 .
共10个数字.
(1)可组成多少个无重复数字的四位数;
(2)可组成多少个无重复数字的五位偶数;
(3)可组成多少个无重复数字的大于或等于30000的五位数;
(4)在无重复数字的五位数中,50124从大到小排第几.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9252cf7f169a57f257ecd8250a89652b.png)
(1)可组成多少个无重复数字的四位数;
(2)可组成多少个无重复数字的五位偶数;
(3)可组成多少个无重复数字的大于或等于30000的五位数;
(4)在无重复数字的五位数中,50124从大到小排第几.
您最近一年使用:0次
解题方法
10 . 已知角
是斜三角形
的三个内角,下列结论一定成立的有( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
A.![]() | B.![]() |
C.若![]() ![]() | D.![]() |
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