解题方法
1 . 已知O,A,B,C四点均在半径为
的球S的表面上,并且满足
,
平面
,
,则三棱锥
的体积为________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e0bac81568b8624599b4b9b39fbae2f6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/886c25cbaff27a9c4cf52dacec0eac4c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4317430d5a2b61d9a2a88b73e7d7ad39.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/daa3a310c1f8a5af35dc3328d874e18e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2166bb9a23c7ed545791eb6b5d66858.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4278c0911e7df78965e78cff69cac5f5.png)
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解题方法
2 . 某商场为吸引顾客消费推出一项优惠活动.活动规则如下:消费额每满100元可转动如图所示的转盘一次(指针停在任一位置的可能性相等),并获得相应金额的返券.若指针停在A区域返券60元;停在B区域返券30元;停在C区域不返券.例如:消费268元,可转动转盘2次,所获得的返券金额是两次金额之和.
(1)若某位顾客消费128元,求返券金额不低于30元的概率;
(2)若某位顾客恰好消费280元,并按规则参与了活动,他获得返券的金额记为X(元).求随机变量X的分布列和数学期望.
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解题方法
3 . 已知
,给出下列四个命题:
:
,
:
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a92956b1693c71902b15e45118c1f87f.png)
:
,
:
,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac624f921a4282e16b160384c47414d0.png)
其中真命题的是( ).
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9994c0aefa7220691dbcb9afa568a182.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2708fa6298e52f617383efc175b71ddc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9309362eb34cd9d0d5757836f8d2fc55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e686113ca2f873c4a911c8c636a39f64.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b9cb8e6ff801523b0304576cd69fd2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9309362eb34cd9d0d5757836f8d2fc55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a92956b1693c71902b15e45118c1f87f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/797e67927616b141ed7c6b83f8b6f4fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c0c5a96a4f87442cbfc05e59de281ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2e3bf4d705125cab1f1868283ffc900f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fee50575e3ebd56c4f46dd0bbf8e55d3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c0c5a96a4f87442cbfc05e59de281ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac624f921a4282e16b160384c47414d0.png)
其中真命题的是( ).
A.![]() ![]() | B.![]() ![]() | C.![]() ![]() | D.![]() ![]() |
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解题方法
4 . 在
中,已知
,若
最长的边长为
,则最短的边长为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c44ca2c5d2835f2555d31a77a8146fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4056761b8f826eeb6ad8c9a151d3c9c.png)
A.![]() | B.![]() | C.![]() | D.![]() |
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解题方法
5 . 已知函数
是定义在R上的函数,且函数
的图象关于点
对称,对于任意的
,总有
成立,当
时,
.函数
,对任意
,存在
,使得
成立,则满足条件的实数
构成的集合为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2c3dd8fa2dc8c0c7e255bfb054ad34c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d7a999c36de5c9a9ce876a4a56fa34c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/42b2897842d014a94af5f74c1c1c6035.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f58427d5aa7deeca47c8789241913f30.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6cf51d9719b5dba6b64411e961002d3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ff8eb3fc5dd80677e2e2e7a3fa6fa68.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24a57996290794e082b21d8f1dfc322a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9bf039c46a25e331446c6ee1e9af3c82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f748c62259e0a54a751cd0670d8f502.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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解题方法
6 . 在
中,
是
的中点,边
(含端点)上存在点
,使得
,则
的取值范围为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b343d64efae317736481ab842450bc1e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/415bd9cdf9fa9312b13a49ea744e2f4b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b32f2d4d1d2c16c54b2caef17840bfcb.png)
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7 . 已知集合
,设
是等差数列
的前
项和,若
的任意一项
,且首项
是
中的最大值,
.
(1)求数列
的通项公式;
(2)若数列
满足
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a101d7fe85109e613e4fdff218e32f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6302fc3e3d1fac960e84950c0e814a19.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8fdbfa7a63fdf5717d40c8c9a73ec160.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b18378ba893f1ce0814c9582699ae29.png)
(1)求数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
(2)若数列
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/034ba25825c13725931c483aa47c9363.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/166e346727bcaf56431b36ef42594af6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b511d10eb2d2d913d7282778206db331.png)
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8 . 在锐角
中,角
所对的边分别为
,且
.
(1)求证:
;
(2)若
,求
的最小值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/76f0649064a085fb74c997fb507a9b6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73871b5eba746c60026c5cce7482d66f.png)
(1)求证:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8636e448103248ddd367d084be0ef715.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c03b5fd68e38254b1e0a9bcd5401c38.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/64da75a02173c2a5eb40f4c68d0f4f36.png)
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9 . 已知函数
的定义域为集合
,又集合
,且
.
(1)试确定
的值;
(2)求参数
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20ac58cf59b80bad283dc6d0d85687cb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff12efce81fd56437c6a436159367cea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ca7953d23f8fd017b4afd51b13b1195.png)
(1)试确定
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/632244ea6931507f8656e1cc3437d392.png)
(2)求参数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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解题方法
10 . 对于任意的
恒成立,则实数
的取值范围为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f4f9a6fc8483bd2b69bf29cb2893a562.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
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