1 . 化简求值:
(1)
,其中
;
(2)
,其中
,
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/583074e2aadc5eb181c2f447c53c1eb2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e9ad96a0492c77ae833043352654a98b.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eba1c26c25e411d61356a4bf7c9324db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/22ff06692c025b869a7bcdcff15dca9e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8d19f95c74f9486638d9d47a0decc20d.png)
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2 . 正方形
,点
分别在
上,
与
相交于点
.
,求证:
;
(2)如图2,平移图1中线段
使点
与点
重合点
在
延长线上,连接
,取
的中点
,连接
,试探究线段
和
的数量关系并证明你的结论.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe2b5c496274a9d822309ab398e7d2fe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/54032a021b8d4976cb9f58477663c9b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1dde8112e8eb968fd042418dd632759e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d34339cd730191fb52b99d0aa1862cb0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e0a0b3a13aff62b214a7b5693fdff7e.png)
(2)如图2,平移图1中线段
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e42887d9bf31c1dd99f13c39e63c9ab9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/73465a1f9aa03481295bf6bd3c6903ac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589786dd7c3a2679c3230b671cd232d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/589786dd7c3a2679c3230b671cd232d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dad2a36927223bd70f426ba06aea4b45.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/85c4bdfb0db1e31e8459df1d15f9ab55.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/48f3c9abbd78e9a6840ee5f30381daac.png)
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3 . 若
,
,则
的值为( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b601d0f382f898200928e025bdf1e622.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f13fcbc469c6061897f8ccb016d1c080.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b88584cf1df43e28d03592c7998b1653.png)
A.1 | B.![]() | C.1或![]() | D.![]() |
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4 . 某学校为了解《大中小学劳动教育指导纲要(试行)》落实情况,就假期“平均每天帮助父母干家务所用时长”进行了抽样调查,如图是根据相关数据绘制的统计图的一部分:
(1)在本次随机抽取的样本中,调查的学生人数是多少人;
(2)求m的值;
(3)补全频数分布直方图;
(4)如果该校共有学生2000人,请你估计“平均每天帮助父母干家务的时长不少于30分钟”的学生大约有多少人.
(1)在本次随机抽取的样本中,调查的学生人数是多少人;
(2)求m的值;
(3)补全频数分布直方图;
(4)如果该校共有学生2000人,请你估计“平均每天帮助父母干家务的时长不少于30分钟”的学生大约有多少人.
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5 . 问题背景:点
分别在正方形
的边
上,
,试判断
之间的数量关系.
小云同学的思路是过点
作
,交
的延长线于点
,如图1,通过这种证明方法,可发现线段
之间的数量关系.请写出这三条线段之间的数量关系,并说明理由;
变式迁移:如图2,在菱形
中,
,点
分别在
上,且
,
,若
,求
的长.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a373959bb9026f8a09845c0b828bf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8dbf16d3adcc74fbea454665bc66ca5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/192155e6a3aade305b76b1eb7c75e30c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/923d96dd27d3dd1a3e265d554b54ea9b.png)
小云同学的思路是过点
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6cfc3169ed1ec9c6db893fff8f53e0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/923d96dd27d3dd1a3e265d554b54ea9b.png)
变式迁移:如图2,在菱形
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a2594e927cb7ed022acc039c3bb136d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6a373959bb9026f8a09845c0b828bf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a8dbf16d3adcc74fbea454665bc66ca5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/adc90c2d45477e166b02359525f40aa6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ebc95af9238cf516b1f60fd4c51b409a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4a9eb456c912e01458c19b06e83a5c9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49b50357a6545cae8348e3059312f520.png)
您最近一年使用:0次
6 . 某服装超市销售10套
型时装和20套
型时装的利润为5000元,销售20套
型时装和10套
型时装的利润为5500元.
(1)求每套
型时装和
型时装的销售利润分别为多少元?
(2)该商店计划一次购进两种型号的时装共120套,其中
型时装的进货量不超过
型时装的2倍,设购进
型时装
套,这120套时装的销售总利润为
元;
①求
关于
的函数关系式(并求出自变量
的取值范围);
②该商店购进
型、
型时装各多少套,才能使销售总利润最大?
![](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)
(1)求每套
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
(2)该商店计划一次购进两种型号的时装共120套,其中
![](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/7f9e8449aad35c5d840a3395ea86df6d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
①求
![](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/81dea63b8ce3e51adf66cf7b9982a248.png)
②该商店购进
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7f9e8449aad35c5d840a3395ea86df6d.png)
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7 . 已知一个正比例函数和一个一次函数,它们的图象都经过点
,且一次函数的图象与y轴相交于
.
(2)在给出的坐标系中画出这两个函数图象.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5cf0417e0f751ebf41c74f65e87d096.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f53f7e6990fc3e24b92ffacc324be35f.png)
(2)在给出的坐标系中画出这两个函数图象.
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8 . 如图,在
中,
,
垂直平分线段
,若
,
.
的长
(2)求
的面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dd967903ed5a6f640a5b801ec8be0070.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7e3262fc038bbec5e7c8cc47df08bef7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e6e490f703eb6c9bb1278c78ebc2d661.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1682d306c38087d9e6f7efb9cec596a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07140f277a35733d8c97577ccdd4e3ab.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
(2)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b5f517953a21c2a45fd8465072c44bfc.png)
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9 . 如图,点
是矩形
的边
上的中点,将
折叠得到
,点
在矩形内部,
的延长线交
于点
,若
,
,则
的长为______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2a30f3a8b673cc28bd90c50cf1a35281.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0dc5c9827dfd0be5a9c85962d6ccbfb1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e742966e3711cfa53dce04022acf4bcc.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca2698f08d94afa1cd5b81444791f4c7.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0ed1ec316bc54c37c4286c208f55667.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6aa2b5e09f8ec785c59900a529390a02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9d78abbad68bbbf12af10cd40ef4c353.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/895dc3dc3a6606ff487a4c4863e18509.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1bdf82f2b3ac77ee7b9b35aebe0dd83f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c68309d3410c05f5675968900e91fbd0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f52a58fbaf4fea03567e88a9f0f6e37e.png)
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10 . 如图,两个较大正方形的面积分别为225,289,则字母A所代表的正方形的面积为( )
A.4 | B.8 | C.16 | D.64 |
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