解题方法
1 . 总结空间线面的垂直关系,怎样判定这些关系?它们之间有什么联系?如何证明性质定理?
您最近一年使用:0次
解题方法
2 . 求证:斜棱柱的侧面积等于它的直截面(垂直于侧棱并与每条侧棱都相交的截面)的周长与侧棱长的乘积.
您最近一年使用:0次
解题方法
3 . 已知点
,
,
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0929421a6188c3122442866b0b85a5e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f55d12701014cf53071093e8739d089b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6481e5ef435b6ad8ecac30175f6871bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/615fc8790237a1b09af51d6bcad6b595.png)
您最近一年使用:0次
解题方法
4 . 求证:
对任意实数
,
,
,
成立,等号成立的充分必要条件
.
提示:(1)以题目中的实数为坐标构造向量
,
,利用坐标计算出向量夹角
的余弦
再代入不等式
;
(2)为什么
?因为
.柯西不等式左右两边之差![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27fb555d58a0abf2991288f733622ec1.png)
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d115a39e93fabee911c86269199e13d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b715e7842b95f654f16056a7c7f2abe9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13423c094861baf4b759b7f3d8c3c226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9490b6aa3c70b2d602ee98369f5aede.png)
提示:(1)以题目中的实数为坐标构造向量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e47852f72902319522dc20d17f7aec2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3bf89b8b4b13539a33c5d7a17800f3e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aefd06c239145a2b6ae87a955aa51414.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed0431cd391637c69a538637ff22d2f8.png)
(2)为什么
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed0431cd391637c69a538637ff22d2f8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6007f5e70739047bdf2d7a44d69cd134.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27fb555d58a0abf2991288f733622ec1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8caeecbfc6645fc3565c4ef2b94bcbd2.png)
您最近一年使用:0次
解题方法
5 . 如图,点A,B分别位于异面直线a,b上,过AB中点O的平面
与a,b都平行,M,N分别是a,b上异于A,B的另外两点,MN与
交于点P.求证:P是MN的中点.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
您最近一年使用:0次
6 . 如图,已知
,作正方形ADEB,BFGC,CHIA.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60c080f62063acfe028208d9b0b40cf4.png)
您最近一年使用:0次
23-24高二上·全国·课后作业
7 . 设圆O的弦
的中点为M,过点M任作两弦
,弦
与
分别交
于点E,F.
的中点;
(2)如果将圆分别变为椭圆、双曲线或抛物线,你能得到类似的结论吗?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5c4cd264c97c1f261229925cc5a6761.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
(2)如果将圆分别变为椭圆、双曲线或抛物线,你能得到类似的结论吗?
您最近一年使用:0次
23-24高二上·全国·课后作业
解题方法
8 . 如图,
是抛物线
对称轴上一点,过点M作抛物线的弦AB,交抛物线于A,B.
,求弦AB中点的轨迹方程;
(2)过点M作抛物线的另一条弦CD,若AD与y轴交于点E,连接ME,BC,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0bbfc5253a678d786c9a8091fff43729.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/745de5ef1fd897d16e37464172d5e8c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e258ab9e600435b37465092243d99f6.png)
(2)过点M作抛物线的另一条弦CD,若AD与y轴交于点E,连接ME,BC,求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/490111e9e5aefb170410f0501134d22e.png)
您最近一年使用:0次
23-24高二上·全国·课后作业
9 . 已知
,
是项数相同的等比数列,求证:
也是等比数列.
![](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/aec4bdc2a6d4fc387dc621f0b5a268c5.png)
您最近一年使用:0次
21-22高一·湖南·课后作业
10 . 已知:
,求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e93622d238a10ef084d02a25e7d6e0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f46c90b74747b4fbe7a10577158e998c.png)
您最近一年使用:0次