名校
1 . 设向量集合
.若对于任意
、
以及任意
,都有
,则称集合S是“凸集”.现有四个命题:
①集合
是“凸集”;
②集合
是“凸集”;
③若集合
、
都是“凸集”,则
也是“凸集”;
④若集合
、
都是“凸集”,且交集非空,则
也是“凸集”.
其中,所有正确命题的序号是________
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37a8aa6b0a40a2ef451c9f6c263662d9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a2f4b1178f68bd147d1a2a6acd04435.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/37c1870a8601323a0fefb2f90c669f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cee72261f6901e62dfd0ffe547406544.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/304c5050fdb05bd5ccdf8bdfc00e8108.png)
①集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9275e06e147f70046e6c91b1cac72bfc.png)
②集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0f32c01a67d79efc9fb98afc8bd2fb8.png)
③若集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3b9e816b14051f785aa5aae72b8eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2646f41226f24960a6186dc7860ef45.png)
④若集合
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a18722354086c42e62334983fc50eb6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd3b9e816b14051f785aa5aae72b8eed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b76d26b78e63683dfacf10d3da6d74d.png)
其中,所有正确命题的序号是
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解题方法
2 . 若α为锐角,且
,则cos2α=( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c40d42418fab54807efb85a00ef8de.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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3 . 函数
(
,
,
)的部分图象如图,
和
均在函数
的图象上,且Q是图象上的最低点.
的单调递增区间;
(2)若
,
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fcd3cea5f5e2fe943490dcb65d74c73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/13378be06b6b01bcad1d261ff14e87cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4456675a5dbe545462a22cef9aca8fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29e1734dcc7697235124fbaba4ba6033.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/083169a97d6babe52eca51c2ed0aefb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8c426f776a2e72a8300512bf52c35ca1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d275fbb3ee5cd1177ca5a2ceecbbef0f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d275fbb3ee5cd1177ca5a2ceecbbef0f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9271992646b7bb71e0841d9d57912cf4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/920f7b809091d270731c50849a4388ef.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/35f8c00c0bf7344ba3bc7984516d3d18.png)
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解题方法
4 . 已知
,
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c44580c3baf0d30acc19e955ad9e324f.png)
______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/665dbee1e961c82bba2218b2c1f07f90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31a48383dab2bf34c13c49cd88f537da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c44580c3baf0d30acc19e955ad9e324f.png)
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解题方法
5 . 在
中,
,
是
的中点,
,则
的取值范围为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffe7a93172d308a58200e3c722fe1072.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/18120a244d3a1f9c1688bf53eb2ad775.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d29c1b36d35c58d2c1a156f488ba7b5b.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
6 . 已知函数
.
(1)求
的图象的对称中心;
(2)当
时,求
的最值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aaea2dbd6d99c8edfb4b2076b7dea385.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/691c1fc50ea793ea08748cb75bae70e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
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名校
解题方法
7 . 我国古代数学家僧一行应用“九服晷影算法”在《大衍历》中建立了晷影长l与太阳天顶距θ(
)的对应数表,这是世界数学史上较早的正切函数表.根据三角学知识可知,晷影长l等于表高h与太阳天顶距θ正切值的乘积,即
.对同一“表高”测量两次,第一次和第二次太阳天顶距分别为
,
,第二次的“晷影长”是“表高”的2倍,且
,则
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/33b13a855bec1e9c264742bbed4685ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd7ba1eba7fba0b56e4e9b4d032e24da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ffb487cd5f8d97cedc263d542caf5bc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73d3a6ba2ae3161cf7c209a30ea464c1.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
8 . 已知函数
,
,下列说法正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/12959f65e9db83c446c35d3261a33171.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbb95686771706d856f67b6a7bc96f5a.png)
A.函数![]() ![]() |
B.函数![]() ![]() |
C.函数![]() ![]() |
D.函数![]() ![]() |
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名校
解题方法
9 . 已知函数
,若存在实数
.满足
,且
,则
的取值范围是_____
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63f0765298b308999e04b74ecb6b579a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e8ccd22fd0ca1a8e1468329284f91b6a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3604274ad6707a906eba371a9e884144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/373a065bb69b411e5107f05d8cb13573.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fc7d6393821d46bcaca5c39b6f5bcb8.png)
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名校
解题方法
10 . 已知函数
,则函数在区间
内零点的个数为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20ef4dbd03c3f454f804890076d9ab79.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad14579830d0293b1390911cb603eb02.png)
A.1 | B.2 | C.3 | D.5 |
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