名校
解题方法
1 . 为了求一个棱长为
的正四面体的体积,某同学设计如下解法.
解:构造一个棱长为1的正方体,如图1:则四面体
为棱长是
的正四面体,且有
.
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/16/6db5d8bf-a942-4eb1-b74e-0d41be5b6734.png?resizew=583)
(1)类似此解法,如图2,一个相对棱长都相等的四面体,其三组棱长分别为
,
,
,求此四面体的体积;
(2)对棱分别相等的四面体
中,
,
,
.求证:这个四面体的四个面都是锐角三角形;
(3)有4条长为2的线段和2条长为
的线段,用这6条线段作为棱且长度为
的线段不相邻,构成一个三棱锥,问
为何值时,构成三棱锥体积最大,最大值为多少?
[参考公式:三元均值不等式
及变形
,当且仅当
时取得等号]
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
解:构造一个棱长为1的正方体,如图1:则四面体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68ac02c2f91cadb1e328bc6ab9b9c491.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf298f00799cbf34b4db26f5f63af92f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6f878ffcff2ca25a434cbeea7d5c841.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/6/16/6db5d8bf-a942-4eb1-b74e-0d41be5b6734.png?resizew=583)
(1)类似此解法,如图2,一个相对棱长都相等的四面体,其三组棱长分别为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2967337e3fcb228dded64ab0c41a17e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50690dab38f4512eb72e18b7f86cf6f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4056761b8f826eeb6ad8c9a151d3c9c.png)
(2)对棱分别相等的四面体
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c220eadc312101e2fb89dfe920f7b30d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7de966c316db1013defc56372fcf814e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8d2530e7023b2345c651e8f53629ff1.png)
(3)有4条长为2的线段和2条长为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
[参考公式:三元均值不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1ffb6b373d2e672bb2afc8de547861a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4849ff71159df2bb9099b26065d81e1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44acc0ee22dc4b7750e8be825e7c1355.png)
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2021-07-15更新
|
814次组卷
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2卷引用:重庆市西南大学附属中学2020-2021学年高一下学期期末数学试题
名校
2 . 某高一数学研究小组,在研究边长为1的正方形
某些问题时,发现可以在不作辅助线的情况下,用高中所学知识解决或验证下列有趣的现象.若
分别为边
上的动点,当
的周长为2时,
有最小值(图1)、
为定值(图2)、
到
的距离为定值(图3).请你分别解以上问题.
的最小值;
(2)如图2,证明:
为定值;
(3)如图3,证明:
到
的距离为定值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6bce3d91ca23b86d8c6625f2632e437.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7473497fee0257402b6318033c1ef7d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d9763846b1131e1e3e2d741ad95d5bb0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/030314ca026d6b18481682f70f48d19b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
(2)如图2,证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/030314ca026d6b18481682f70f48d19b.png)
(3)如图3,证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a5f1641947153c80b987320885a2b57.png)
您最近一年使用:0次
2024-05-08更新
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277次组卷
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2卷引用:广东省江门市某校2023-2024学年高一下学期期末热身模拟数学试题
3 . 同余定理是数论中的重要内容.同余的定义为:设a,
,
且
.若
则称a与b关于模m同余,记作
(modm)(“|”为整除符号).
(1)解同余方程
(mod3);
(2)设(1)中方程的所有正根构成数列
,其中
.
①若
(
),数列
的前n项和为
,求
;
②若
(
),求数列
的前n项和
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/538f8c7f224b743a48128033066b34cc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f6b18b109a656b62fb173680ae99ca7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e34f42b3be15518c29e3689c9fe6d6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/58d71082924d5b4349c3b0152930b7b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a07e47345c46575e63ff4c3df4557bc.png)
(1)解同余方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44b31b29e7f0705c981bd91329bcfee7.png)
(2)设(1)中方程的所有正根构成数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c002c44d45907aad22da19859193270b.png)
①若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5653b60d16ec4e653518f0562680250.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37a59558292ad6b3d0978bfd7484990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/addee6ce5163a2580888ce2da22714af.png)
②若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91ac8a1dc1eda952f7145a08c047ebf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a37a59558292ad6b3d0978bfd7484990.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57ef6d44448092ebdb9e4a49d866a749.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1ae9a3b0b7aeb1545b65d91aa371b3c.png)
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2024-02-03更新
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9卷引用:安徽省合肥市第一中学2024届高三上学期期末质量检测数学试题
安徽省合肥市第一中学2024届高三上学期期末质量检测数学试题湖北省武汉市华中师大第一附中2023-2024学年高二下学期数学独立作业(一)(已下线)压轴题函数与导数新定义题(九省联考第19题模式)练(已下线)新题型01 新高考新结构二十一大考点汇总-3重庆市万州二中教育集团2023-2024学年高二下学期入学质量监测数学试题(已下线)黄金卷08(2024新题型)(已下线)题型18 4类数列综合浙江省部分学校联考2024届高三高考适应性测试数学试题广东省揭阳市普宁市华美实验学校2023-2024学年高二下学期第一次阶段考试数学试题
4 . 已知向量
,
.设函数
,
.
(1)求函数
的解析式及其单调增区间;
(2)设
,若方程
在
上有两个不同的解
,求实数
的取值范围,并求
的值.
(3)若将
的图像上的所有点向左平移
个单位,再把所得图像上所有点的横坐标伸长为原来的2倍(纵坐标不变),得到函数
的图像.当
(其中
)时,记函数
的最大值与最小值分别为
与
,设
,求函数
的解析式.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e799f96093d8bfb6b5a6709ec6c4f60.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/946b48a52deb8046aa914743976d585d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/19eec7b3f71103529d3e40a5fa885663.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a57996290794e082b21d8f1dfc322a.png)
(1)求函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e101a51a158ada412cb00e8eccdcaf90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d5226dd4e2d35264cf06db4af3b103a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ac075691407fc7a2eb3fcd3dc372d2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd8ca3aa2d1ba52e82613d0d65d800e7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a0862ffea88e467274cadae1d43aaae.png)
(3)若将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af9955b5aebb73cd84447e8541f901ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0eb7df298a9364b36e079a61caec815c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4091db0afc745453052bf2cdb2b6b27b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa340e78e904cbfad040973ea75f3c0a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0eb7df298a9364b36e079a61caec815c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97375cc323000d47f4809130084d0794.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38ab787a669e0df3c59b7251ea61ebee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9a3e257ee2da131c8886346192dcd48.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae4b8114fcc770a8512cf03da137ca4e.png)
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2023-03-26更新
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2卷引用:江西省抚州市资溪县第一中学2022-2023学年高一下学期7月期末考试数学试题
解题方法
5 . 已知函数
与函数
有相同的极值点与极值.
(1)求a,b;
(2)若方程
与
分别有两个解p,q(
)和r,s(
).
①分别用p,q表示出r,s;
②求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb7275d5d8dc96e8f717905b3b829917.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/477bdd62660801ac1dfa2d60ba333cd6.png)
(1)求a,b;
(2)若方程
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9c0d827ef8598ba6b70b34b2bdcd1e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2818807dce7e9ec5514de572c3cc644.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4610754dff007c541aa4887d8705329.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b25109e1cbcdb7f8cedd0422525a1cdb.png)
①分别用p,q表示出r,s;
②求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d2c12355c99c2e113b23e748b768eaf.png)
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