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1 . 如图,一条东西流向的笔直河流,现利用监控船
监控河流南岸的
、
两处(
在
的正西侧).监控中心C在河流北岸,测得
,
,
,监控过程中,保证监控船D观测A和监控中心C的视角为
,A,B,C,D视为在同一个平面上.
的长度;
(2)记
的周长为
,
,试用
表示
,并求
的最大值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.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/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c284ccb6f4ee7a8690013d2ce16e226.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb3f8cb648966fd4ff28896fe8f9e04d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27804d779285035ff8a3b9b1332d0178.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c0927afc571a7c966c98192040979e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
(2)记
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7ac5396c5ea442e0364b50c1db3d2da.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8cc5e8fc797a3a45c253b783631d4e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
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解题方法
2 . 为了丰富同学们的课外实践活动,某中学拟对生物实践基地(△ABC区域)进行分区改造.△BNC区域为蔬菜种植区,△CMA区域规划为水果种植区,蔬菜和水果种植区由专人统一管理,△MNC区域规划为学生自主栽培区.△MNC的周围将筑起护栏.已知
m,
m,
,
,设
.
m,求护栏的长度(△MNC的周长);
(2)试用
表示△MNC的面积,并研究△MNC的面积是否有最小值?若有,请求出其最小值;若没有,请说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd0566be94b1ed3e5d250ca530eeb529.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3dd4997da49b3dfe98144ad13aed0d5c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b57fdd2a3642716fcf5100011eb3ec88.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5cf48407af008db11eb4f236691d741.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bd66efa75728f06d56c53886b58424c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fbb12ea3cc86c6d177447ec2a222ffd7.png)
(2)试用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
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3 . 为了迎接4月23日“世界图书日”,宁波市将组织中学生进行一次文化知识有奖竞赛,竞赛奖励规则如下,得分在
内的学生获三等奖,得分在
内的学生获二等奖,得分在
内的学生获一等奖,其他学生不得奖.为了解学生对相关知识的掌握情况,随机抽取100名学生的竞赛成绩,并以此为样本绘制了如下样本频率分布直方图.
(1)求
的值;若现从该样本中随机抽取两名学生的竞赛成绩,求这两名学生中恰有一名学生获奖的概率;
(2)若我市所有参赛学生的成绩
近似服从正态分布
,其中
,
为样本平均数的估计值,利用所得正态分布模型解决以下问题:
①若我市共有10000名学生参加了竞赛,试估计参赛学生中成绩超过79分的学生数(结果四舍五入到整数);
②若从所有参赛学生中(参赛学生数大于
随机抽取3名学生进行访谈,设其中竞赛成绩在64分以上的学生数为
,求随机变量
的分布列.
附参考数据:若随机变量
服从正态分布
,则
,
,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e77699e3d1ddc6e698a640573a7ef787.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d90faf85d1548242098a6fe3accd84f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3dd615c194ebc63b5219cbbcafd53448.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/6/4/8db1b64f-49d1-4628-afb8-997028fc8d06.png?resizew=274)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
(2)若我市所有参赛学生的成绩
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e84c2c26cbb6b22a415fd0830401aeac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/57db59c20e7a352a161bc589d36938e8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1100379a4385b9ce064847bc21760adc.png)
①若我市共有10000名学生参加了竞赛,试估计参赛学生中成绩超过79分的学生数(结果四舍五入到整数);
②若从所有参赛学生中(参赛学生数大于
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b73562b96751d4c368f9ac97f3d88667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b734e8f1546481e3eb4976008a045de.png)
附参考数据:若随机变量
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e84c2c26cbb6b22a415fd0830401aeac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/256181dd02e41f3a9eadf1de097f472e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cee36a73c750c9229a4a4f4683cbcd3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8978e75d27c4ccd0b211326ac932e17.png)
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4 . 某公司为监督检查下属的甲、乙两条生产线所生产产品的质量,分别从甲、乙两条生产线出库的产品中各随机抽取了100件产品,并对所抽取产品进行检验,检验后发现,甲生产线的合格品占八成、优等品占两成,乙生产线的合格品占九成、优等品占一成(合格品与优等品间无包含关系).
(1)用分层随机抽样的方法从样品的优等品中抽取6件产品,在这6件产品中随机抽取2件,记这2件产品中来自甲生产线的产品个数有
个,求
的分布列与数学期望;
(2)消费者对该公司产品的满意率为
,随机调研5位购买过该产品的消费者,记对该公司产品满意的人数有
人,求至少有3人满意的概率及
的数学期望与方差.
(1)用分层随机抽样的方法从样品的优等品中抽取6件产品,在这6件产品中随机抽取2件,记这2件产品中来自甲生产线的产品个数有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f022950e0faa45b617d497b01b5292b9.png)
(2)消费者对该公司产品的满意率为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b2a698891d42c70b597f0da4f215f09.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54a829fdd8ec0f3b7ede883cf2c3e53b.png)
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5 . 如图所示,某海域在A,B两处分别设有停靠码头,B在A北偏东30°相距
海里处,现由甲,乙两艘货船分别从A,B两处向C处航行.甲货船从A处以
海里/小时的速度沿着正东方向行驶,乙货船从B处以3海里/小时的速度向沿东偏南45°的方向行驶,当航行至1小时,甲货船到达E处,乙货船到达F处,此时乙货船因故障停止航行并发出求救信号,甲接到信号后立即掉转方向并以
海里/小时的速度行至F处施展抢修工作.
(2)若抢修工作共经历1小时,抢修结束后乙船仍以原速度驶向C处,则自乙船从B处出发到乙船行至C处为止,共经过了多长时间,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6214381b57afa4c26e6074251279294f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/95bacae35b6e16a0a33c2bdc6bc07df7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/38387ba1cadfd3dfc4dea4ca9f613cea.png)
(2)若抢修工作共经历1小时,抢修结束后乙船仍以原速度驶向C处,则自乙船从B处出发到乙船行至C处为止,共经过了多长时间,
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6 . 佛山电视塔位于文华公园内,是佛山地标性建筑.某位高中生想运用所学知识测量验证一下高度,通过查阅资料获取了两种测量方案.
方案一(两次测角法):如图一,在电视塔附近广场上的
点测得电视塔顶部的仰角为
,正对电视塔前进
米后,到达
点,在
点测得电视塔顶部的仰角为
,然后计算出电视塔
的高度.
上,人后退至从镜子中恰能看到电视塔的顶部位置,测量出人与镜子的距离为
米;②正对电视塔,将镜子后移
米,重复①中的操作,测量出人与镜子的距离为
米,然后计算出电视塔
的高度.
实际操作中,方案一测量数据为
米,
,测得电视塔高度为
;方案二测量数据为
米,
米,
米,测得电视塔高度为
;假设测量者的“眼高
”都用1.6米.
(1)用
表示
;
(2)计算
的实际测量值(参考数据:
,结果保留整数).
方案一(两次测角法):如图一,在电视塔附近广场上的
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5873c01192b7d33b7483f444f90b5b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77ab1256702aef4e9f1a5eb6c12ecc96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fbd67f60f04c278bdd867fdb3979dfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
实际操作中,方案一测量数据为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73c522cf3ce31023117b820d740ea808.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2b0abd270561207b14cc5115fac5611.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86163e76653de1f383788b741fb64a8b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cb3f1e71282d682759b6ecdb30d4e84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3539abea2f5c8f31a2a4ea1aa9590f7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf6c6385714af1f014af72c805cc9679.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e1fae01485740cbb48b5c79f1185b54.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3eabd5f3a86afe49dcd70571e2b96cfd.png)
(1)用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/401d3aa40316c9c1608ba185655f7889.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/86163e76653de1f383788b741fb64a8b.png)
(2)计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45eb4c210d02b62d0d45cbf83a052dbf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/605382b51597578bda41e7f114ac113b.png)
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7 . 已知
,
与
的夹角为
,
为
外接圆上一点,
与线段
交于点
.
,求
;
(2)设
.
(ⅰ)试用
的函数表示
;
(ⅱ)求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89d64255de7162b1fa5f659732693daa.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4f605ec0729ce6d72237ad662a06862.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6fc9656d8286c4d6fa309d6ae347c89e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2b83beedb3438153e6f728545fe3e03.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/828628c0876b45381c9a0edeb0fec236.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a41a475407451ed8427d0e7a483568c5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6eff576db012cc8a793b1afcb0b47fbe.png)
(2)设
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f7983aade7a7c61f065c5bd3569fbd2.png)
(ⅰ)试用
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c24095e409b025db711f14be783a406c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/72f14d13e081ed59bab413a9f30b62e3.png)
(ⅱ)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e5ef6d007c9539c08562fcc217ae131e.png)
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8 . 某同学用“五点法”画函数
在某一个周期内的图象时,列表并填入了部分数据,如下表:
(1)请将上表数据补充完整,并求函数
的解析式;
(2)将函数
的图象向左平移
个单位后,得到函数
的图象.若方程
在区间
上有解,求
的取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6157ef443108dda491868c1a96e3c8e9.png)
![]() | 0 | ![]() | ![]() | ![]() | ![]() |
![]() | ![]() | ![]() | |||
![]() | 0 | 3 | ![]() | 0 |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/09f86f37ec8e15846bd731ab4fcdbacd.png)
(2)将函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/942c2141d01bde6b48210c56a17fc75e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac1a63ab608517bb10aa036783dfb51f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1938c093dd2fbcb752d0eb7a18d143b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d873ccbd26127bb543951eff8af9337.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1a908cff3963ed5281930402c853b0b0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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解题方法
9 . 记
的内角
的对边分别为
,已知
的面积
.
(1)求
;
(2)若
,求
;
(3)若
,且
存在最大值,求正数
的取值范围.
![](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/15c0dbe3c080c4c4636c64803e5c1f76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8e756d5553e27d8535f4204ce539dc39.png)
(1)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aeb681f294c01e9e2a14503035581bce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
(3)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f002f960ec07ea229ed243e2d991d83.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9a7ff617b214b15e6838b81ac21db8bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df64046e91b047037f19e4032e3b6de3.png)
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解题方法
10 . 已知向量
.
(1)若
,且
,求向量
的坐标;
(2)若
,且
三点共线,求实数
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cd563b0fa52b0581f1327ee012c854b2.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/547485e91d0fef83e879f6306c3decb5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a3765851ae15bd5568ec4462c3f9aa7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73a0b19e69be46452425916a0fcb49c9.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bc10093092181ecdbb834fdeeffbf72.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/24e0c10fb103930eabd5fa18e8f9bb06.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
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