名校
1 . 由于四边形不具有稳定性,所以求四边形面积公式需要有限制条件.我们将四个点在圆上的四边形称为圆内接四边形,圆内接四边形具有对角互补的性质.印度数学家婆罗摩笈多发现了圆内接四边形的面积公式为
,其中
、
、
、
分别为圆内接四边形的4条边,
,与海伦公式有类似之处.已知在圆内接四边形
中,
,
,
,
,则四边形
的面积为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/26f9a99467e1c9715852266155be6a9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c94bb12cee76221e13f9ef955b0aab1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/071a7e733d466949ac935b4b8ee8d183.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c02bc0c74292b1e8f395f90935d3174.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/575008e0b065f0d535251a041203f99f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/efc6e4b936d7a800e839a30c3839574d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e65a3e478bb87d094e3a0af30dd10ae8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b515965c22d2950b592c096c6e3bdfd4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bcffaa7a79cedadb925149e28e39a43.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
您最近一年使用:0次
2 . 如图
是由两个三角形组成的图形,其中
,
,
,
.将三角形
沿
折起,使得平面
平面
,如图
.设
是
的中点,
是
的中点.
与平面
所成角的大小;
(2)连接
,设平面
与平面
的交线为直线
,判别
与
的位置关系,并说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b1527ab37e0ce210fac7fa0164afde5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a43fcce40446633bf9e0b7a9acf58052.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8520a21b909d04f763d0f61dd74bc158.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb90428135c2058f07e2c798f71b5b71.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6d077f6da8b2c00b152d4679aa2ed7f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/60ef95894ceebaf236170e8832dcf7e3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/20a541b81584a032f571159ea152c85a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0628681907ac8d7fdb94d8bc1b15feb9.png)
(2)连接
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2be49c37e30a3ced0364c3e74d8c687.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2f493fa40faff9c21b7aedca05de9379.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7b7c83470489253394bd288d7c920df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f85fca60a11e1af2bf50138d0e3fe62.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
您最近一年使用:0次
3 . 如图,在直角三角形
中,
,
垂直于斜边
,且垂足为
,设
及
的长度分别为
和
,
是
的中点,点
绕点
顺时针旋转
后得到点
,过
点作
垂直于
,且垂足为
.有以下三个命题:
①由图知
,即可以得到不等式
;
②由图知
,即可以得到不等式
;
③由图知
,即可以得到不等式
;
以上三个命题中真命题的是______ .(写出所有正确命题的序号)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7bef5239ddbb0972700ce01daf9ee7cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6f8e9ec412ea0355e4e5cd06c60e5fee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03902478df1a55bc99703210bccab910.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d40b319212a7e7528b053e1c7097e966.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a6936d370d6a238a608ca56f87198de.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e87f673c8f5c214d1e59bfe21fe82397.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b2ff7caec4fdd8fb54a3ffbff9692414.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7e4fa04825ac7d071968056322d88be.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/68a83fdd2ba72a2dba0b6b10bb3e06b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
①由图知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/31367f0685c866fb013012c699803a35.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/160414ad552f0f114a6bc92bcf000270.png)
②由图知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f7ffac6c07b3208f1ab97386df03b617.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b22fa0018340c11558c0ef8dbe422cb0.png)
③由图知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ddff7f3e7ba78336d8b9d96d0065e1db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/516372020f70ab0b86e02f96f3e684e1.png)
以上三个命题中真命题的是
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/26/e5b38708-1c30-46c5-b816-773546683593.png?resizew=188)
您最近一年使用:0次
4 . 要建造一面靠墙、且面积相同的两间相邻的长方形居室,如图所示.已有材料可建成的围墙总长度为30米,宽为
米,居室总面积
平方米.
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/25/85b51198-47ac-4f53-a72a-45b6262ec03a.png?resizew=188)
(1)若居室总面积不少于48平方米,求
的取值范围;
(2)当宽
为多少米时,才能使所建造的居室总面积最大?
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/25/85b51198-47ac-4f53-a72a-45b6262ec03a.png?resizew=188)
(1)若居室总面积不少于48平方米,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(2)当宽
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
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解题方法
5 . 下列命题中正确的是( )
A.若![]() ![]() ![]() |
B.若![]() ![]() ![]() |
C.若![]() ![]() ![]() |
D.若![]() ![]() ![]() |
您最近一年使用:0次
解题方法
6 . 已知幂的基本不等式:当
,
时,
.请利用此基本不等式解决下列相关问题:
(1)当
,
时,求
的取值范围;
(2)当
,
时,求证:
;
(3)利用(2)证明对数函数的单调性:当
时,对数函数
在
上是严格增函数.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d33da711e50e96568facb18cef27165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1419108104429f6df5d5352a05211e36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db5e0630a1632f6368fb824ebfdead0d.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7326ea56be82bd616fec7e6aa3c884c8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1419108104429f6df5d5352a05211e36.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca16bee4a8ecee60c31f9aaac02539b0.png)
(2)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d33da711e50e96568facb18cef27165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27eb687fdf1568ab06ce8119845823c9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c92098b3da769963a2320cf1d8dad00a.png)
(3)利用(2)证明对数函数的单调性:当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1d33da711e50e96568facb18cef27165.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/82869dad28f771d088772a2c2b08b187.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d562dc22dfb3b81d0c3f88b54d063c2f.png)
您最近一年使用:0次
解题方法
7 . 数学上,常用
表示不大于x的最大整数.已知函数
,则下列四个命题:
①函数
在定义域上是奇函数;
②函数
的零点有无数个;
③函数
在定义域上的值域是
;
④不等式
解集是
.
以上四个命题正确的有( )个.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c4f5908d6a1217e493ed7586b6964dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cd671d0910eb818fc35b2df2a7151ed.png)
①函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cd671d0910eb818fc35b2df2a7151ed.png)
②函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cd671d0910eb818fc35b2df2a7151ed.png)
③函数
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5cd671d0910eb818fc35b2df2a7151ed.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/455ba3d3e46977fcbe5b71f8bb9df4be.png)
④不等式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/59362a09f87ca6aa40f1a66439e4f198.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5e58768fc0df02f60aa54d00fe063c52.png)
以上四个命题正确的有( )个.
A.0 | B.1 | C.2 | D.3 |
您最近一年使用:0次
解题方法
8 . 某连锁便利店从
年到
年销售商品品种为
种,从
年开始,该便利店进行了全面升级,销售商品品种为
种.下表中列出了从
年到
年的利润额.
(1)若某年的利润额超过
万元,则该便利店当年会被评选为示范店;若利润额不超过
万元,则该便利店当年不会被评选为示范店.试完成
列联表,并判断商品品种数量与便利店是否为示范店有关?(显著性水平
,
)
(2)请根据
年至
年(剔除
年的数据)的数据建立
与
的线性回归模型①;根据
年至
年的数据建立
与
的线性回归模型②.分别用这两个模型,预测
年该便利店的利润额并说明这样的预测值是否可靠?(回归系数精确到
,利润精确到
万元)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/442470e2e4b15229eefd5c2b19d01932.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6567511bb9486b2ca7452b870abd2a1f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4abb59695562b3a1295a251dc97da700.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f95463e4696bcb6ed28581bad689d0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cfce2106c9ad85e4965af5d95c9bf4d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/442470e2e4b15229eefd5c2b19d01932.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e946baf1316ac1f219398ecedadf6cf.png)
年份 | ||||||||||
利润额
|
(1)若某年的利润额超过
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae4e4c36a1ec6021c9056d8a05bafd34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ae4e4c36a1ec6021c9056d8a05bafd34.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b72fcdc709e77910cd36a26369648b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ead9d6ff51996f3ebace6f212e11a9e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a93888a85455e51d2f0d21e34263d7b5.png)
品种为 | 品种为 | 总计 | |
被评为示范店次数 | |||
未被评为示范店次数 | |||
总计 |
(2)请根据
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/442470e2e4b15229eefd5c2b19d01932.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e946baf1316ac1f219398ecedadf6cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d01dd350dc95f42f1883e0cc7aae084.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4f95463e4696bcb6ed28581bad689d0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e946baf1316ac1f219398ecedadf6cf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8e8936c9fe1e81726455908657a29fc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/042e234d538bc2c789d7c5a314f1ca92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a87796ee30e6c5d5e6b6285b32abe10c.png)
回归系数与
的公式如下:
您最近一年使用:0次
9 . 已知等差数列
的前
项和为
,且关于正整数
的不等式
与不等式
的解集均为
.
命题
:集合
中元素的个数一定是偶数个;
命题
:若数列
的公差
,且
,则
.
下列说法中正确的是( )
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6dd446ae199f91a9ccbc9f8e4d9bb929.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fd282f6c75c2b717aa5d00db9140a5f2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
命题
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e170f206fdbbd834aad7580c727e2cc6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ac047e91852b91af639feec23a9598b2.png)
命题
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b5858ee1ce52b251816757257a11c29.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83cf38189d5cbf627d2b82ac0eb76006.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c4ce64685821c3e55c07f151996ca8c3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ddc7d0838efcb0215d4237ebd210f4f7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7dd8cb812f7bdf482a0ae71a0eb5c0c7.png)
下列说法中正确的是( )
A.命题![]() ![]() | B.命题![]() ![]() |
C.命题![]() ![]() | D.命题![]() ![]() |
您最近一年使用:0次
10 . 已知方程
,且
,
是方程的两个不同的实数根.
(1)若
,求
的值;
(2)若
,且
,求
取值范围.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c256c024fa43ed74983bf0f56144313.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec19b68e3add9d5bfcc6269a1855b87.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b9034c939a8705eae3bbb55b290a2f85.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54e4c4e9e08e93cc72210dce79effcea.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/df307146ad61d4bf105370f65a3e742c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/87fd4ab15eb115aa5bb496fde7b7130e.png)
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