1 . 设
是一个有
元素的集合,
的
个子集
两两互不包含.试证:
(1)
;
(2)
.
其中
表示
所含元素的个数,
表示
个不同元素取
个的组合数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1835aeec021f7386dd12faf0b45eced5.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46bafe6c0781a2bc981edb9abcadcd7f.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64792e1abeaa1faee738528d416d8154.png)
其中
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa9ca68ba83be22ec5cbd6eba191cbc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e819b87f90651d89fcd258c276294e43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/742812cc958b52f5a8211f7c1968a785.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fa9ca68ba83be22ec5cbd6eba191cbc6.png)
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2 . 以椭圆
的长轴为底的内接梯形最大面积是.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7aea48c44781a844b5c19191f70f61.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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3 . 设实数
、
、
、
满足
,
,
.求证:
.
![](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/df64046e91b047037f19e4032e3b6de3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22353d75e8b484914c003fadefcf046e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eed2abb5239389eb8254550bff6a6687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66e4869e5bf056f8a2e7c2b1fa1a20b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9e06197242f03fbb260a2e0bf127193.png)
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4 . 给定平面上
个相异的点,证明:其中距离为1的点对不超过
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ac19e2a797cd0a408316988a63b3755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7959b1b68a2b7e09451ae66ffaf4b0b7.png)
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5 . 设
,
,且
.记
.证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/457f27093741e41143685184bae0a379.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5576806dd0c4b3fb0cdd2ce461f0671.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfe3caff2460a3e4c9961b2e0fa5fc3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0094deac0b1c20ee76d339f571375791.png)
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6 . 对正实数
.求证:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7f5573b30734d65648f61c0a94c98de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ce522c192db05fa6c07360a5aff501e.png)
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7 . 设
.证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/713d0322016f5d4dcb7255e8845d3b5a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46ffacceaefd6853e061e8ecd5fa2c79.png)
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8 . 在
中,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1beca577571e38d9c18d0f7a768eca51.png)
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9 . 设
,且
求
的最大值与最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6bbbfd88c06682d8ae00dd9b9f90ca94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b94686039124976778f6f24fd6d1ae2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc584fa00d7b1358d06df9ab1b19539.png)
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10 . 函数
的最大值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e36913a621f7e33f9277cb0611208a7.png)
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