1 . 已知点B在点C正北方向,点D在点C的正东方向,
,存在点A满足
,则![](https://staticzujuan.xkw.com/quesimg/Upload/formula/451edc75de74313e53f5d636ac930848.png)
______ (精确到0.1度)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5a16dc02090b6e9263555061f14fbc8c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d381171dbde5c1ff4d8a09c178ab6f4a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/451edc75de74313e53f5d636ac930848.png)
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2 . 已知向量
,
,定义运算
,同时定义
.
(1)若
,求实数
的取值集合;
(2)已知
,求
;
(3)已知定义域为
的函数
满足
为奇函数,
为偶函数,且
时,
,是否存在实数
,使
?若存在,求出
的值;若不存在,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7ec6dba44a83ae69146c26a2eec325c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/66717aa3e7a771427c1d4433c77a5e29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4817c9821c3c5268e665a3ebcfe2e9cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/153f8261059b286d175e53adb666d0bd.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e993a236a70e4a094013a28c07079f84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/237b1a6f3e6ee0ef92b4aef7bffe58ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b5285f8cfbab2baf73267d7649a58ac.png)
(3)已知定义域为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43b2faa4f81f32d94612dce724e772b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0eb7df298a9364b36e079a61caec815c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/91340ce6d32493c33527a32c2d448896.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ffde73ff7d3cd5125eb8d8a17a9f01c1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/994dcf841d356002fcebaed37497013c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de03de9f4bea859252f0158b32acf378.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2bb0b435b3f1a00ee1df0d02384d6e57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
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解题方法
3 . 下列说法不正确的是( )
A.函数![]() ![]() |
B.函数![]() ![]() ![]() |
C.若![]() ![]() |
D.函数![]() ![]() |
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解题方法
4 . (1)已知函数
,证明:
,
,
.
(2)已知函数
,定义:若存在
,
,使得曲线
在点
与点
处有相同的切线
,则称切线
为“自公切线”.
①证明:当
时,曲线
不存在“自公切线”;
②讨论曲线
的“自公切线”的条数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ff6838d84b68c6f0d3b93b196d9b08d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/673207f6b77b8192d25463d071737b7c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b1bf60c5e8996d138198fe74f30ce520.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9da092efa74406128332df5a053685a8.png)
(2)已知函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1aba730d4e2ff4c9cc155446b3d12e96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85a93969738a9bb969f40cf587f1d5d5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/878fd4af5b8fff01627f560767e19b73.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4197070db34f0419b6d85eed4cec9fc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
①证明:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08115d6d9f876dea921a4d32260ff1fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
②讨论曲线
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
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5 . 某公司为了解年研发资金
(单位:亿元)对年产值
(单位:亿元)的影响,对公司近8年的年研发资金
和年产值
(
,
)的数据对比分析中,选用了两个回归模型,并利用最小二乘法求得相应的
关于
的经验回归方程:
①
;②
.
(1)求
的值;
(2)已知①中的残差平方和
,②中的残差平方和
,请根据决定系数选择拟合效果更好的经验回归方程,并利用该经验回归方程预测年研发资金为20亿元时的年产值.
参考数据:
,
,
,
.
参考公式;刻画回归模型拟合效果的决定系数
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/97ea8f47d8d8d9e1832d52b1c7425450.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4de122ae929b1acaff321dec137622ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e2928f2bf2a086d6301b5352f7ef1aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ac190405449cba34174ed6705aa6ba.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/718cfed01c71b2fc805d8d7100b91dc5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c676941ea413d829060d29befd59d554.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5292c735338a9c57f86b2b2442261bef.png)
(2)已知①中的残差平方和
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/44f23c3d6eb2728ae5c1171eac969b09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4515125add629aa249ac0e14f01b257.png)
参考数据:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/194bfb08c0f47c01de5bfe5660d423a6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/788b03267c223ba0538552371aa1a31b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/748e20fa23b995da6aa1c5936bf38117.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f4cbe45f8c50795b37c9925414ea816.png)
参考公式;刻画回归模型拟合效果的决定系数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72c8cd473a8b5a8da1f04b5041e609b0.png)
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6 . 学校将先后组织篮球和足球比赛,需要体育协会的同学来当裁判员.已知8名体育协会的同学中,有6人能胜任足球裁判,4人能胜任篮球裁判,现需要篮球,足球裁判各3人,则一共有_________ 种安排方法.
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解题方法
7 . 长方体
中,
.
(2)记(1)中截面为
,若
与(1)中过
点的长方体的三个表面成二面角分别为
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adddcf2b210fdeda3e7795e779bd86aa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e30816e31c2f392a4c975d539b458d89.png)
(2)记(1)中截面为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6a1f9f284b23e927ccffd063cb2d4ea.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dbbde2388c030a896c364e62675190d.png)
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8 . 已知方程
,下面四个命题是真命题的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/608e3b6e18246d45521a240b5bfc5009.png)
A.当![]() |
B.当![]() ![]() |
C.当![]() |
D.当![]() ![]() |
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9 . 已知曲线
与
,下面结论不正确的是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af2574349f25cec9c0e9c0f001989ac1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ef3681fa214c32fcd1a498e3ae441627.png)
A.![]() |
B.![]() ![]() ![]() |
C.不等式![]() ![]() |
D.记点![]() ![]() ![]() |
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10 . 海宝塔位于银川市兴庆区,始建于北朝晚期,是一座方形楼阁式砖塔,内有木梯可盘旋登至顶层,极目远眺,巍巍贺兰山,绵绵黄河水,塞上江南景色尽收眼底.如图所示,为了测量海宝塔的高度,某同学(身高173cm)在点
处测得塔顶
的仰角为
,然后沿点
向塔的正前方走了38m到达点
处,此时测得塔顶
的仰角为
,据此可估计海宝塔的高度约为__________ m.(计算结果精确到0.1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/29e0c2455a9e796bba6861503f0fe31b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6ea06b78df3f0847f358714357a18d30.png)
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