1 .
,求所有的
,使得
中有无穷多项为正整数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fad039ab9ca99b3d62b798884e8988b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/629507dcfdeb6866da428c4f45e2b21d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
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2 . 设球在圆柱内,且圆柱的底面直径和高都等于该球的直径,则球与圆柱的体积之比是______ .
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解题方法
3 .
为正实数,满足
,求
的最大值
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/751e274e9107d780c39ba9c49d6daefb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c19cb3b888b46a0c5e62ccbb09bd77ba.png)
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解题方法
4 . 双五棱锥是由两个侧面均为边长为1的正三角形的五棱锥上下拼接而成的,如图所示.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/17/7b4e1fa0-9c3c-43ca-b5b3-188c8bc7d378.jpg?resizew=133)
(1)求双五棱锥的内切球半径;
(2)求分别位于拼接面(正五边形)两侧的相邻的两个正三角形构成的二面角的余弦值.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/3/17/7b4e1fa0-9c3c-43ca-b5b3-188c8bc7d378.jpg?resizew=133)
(1)求双五棱锥的内切球半径;
(2)求分别位于拼接面(正五边形)两侧的相邻的两个正三角形构成的二面角的余弦值.
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解题方法
5 . 如图,已知三棱柱
,
平面
.D,E分别是
的中点.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/22/03e0cf8e-497b-4d52-a9f4-08f68e020eed.png?resizew=177)
(1)证明:
平面
;
(2)设
与平面
所成角的大小是
,若
,证明:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42d3a82b8e587ee890467835bc4e854c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d1d2e0f281222a5f289ea4008370aed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1cc117eb1a2d0ea7123b2ca898547546.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/310e5cf87aa443ca7f0ff80aba6dddc4.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/2/22/03e0cf8e-497b-4d52-a9f4-08f68e020eed.png?resizew=177)
(1)证明:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/063510e3c1fb6a7ccc3b8e3e3c7d660e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/99b16cff607cdc2d69afc70dc778acbb.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24bb49fdc6b6bbb2449fdf8a0de769d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab3e0dba5705e1d749cfb21ebbb2ed93.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a8670759c61d785b9a336885df700b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb2cf0e95fdf1fd8a5b01d3dfd905e08.png)
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解题方法
6 . 设
,
,
,则( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b51358c6fd18265f9e3eb8a251bdeb63.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d13ac5fd914eb4f6d6be440255ed5f6e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d24a4a2ddd7e3bc197149ec67fc5b56b.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
7 . 方程
的实数解的个数是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6974a4b501d7523bc7b61b41c98a9e1e.png)
A.0 | B.1 | C.2 | D.3 |
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8 .
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dc6a0713917c995c9cba31fdab2bd766.png)
A.![]() | B.0 | C.1 | D.2 |
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解题方法
9 . 给定
,若
,
满足
,均有
,则k的范围是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5aff8d9b6533ff319420cdc5e8740b04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/756cd04fb04459ef15b1d37c9bb88e9a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2671f593186fa00f17ad26eba7b8f3e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe383188576e4de78241ddaf8cf94144.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d3481d657e1d1ca13aa4ad8af6b4afd.png)
A.![]() | B.![]() |
C.![]() | D.![]() |
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10 . 使
恰有2个整数解的正整数n的值为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7db6187cc7a8e5c863f95fa721065f8b.png)
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