1 . 如图,我们可以用长度相同的火柴棒按一定规律搭正多边形组成图案,图案①需8根火柴棒,图案②需15根火柴棒,…,按此规律,第
个图案需要_________ 根火柴棒,第2022个图案需要_________ 根火柴棒.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/2/24/851d7c49-7bab-469e-b4b8-14f0531786c2.png?resizew=348)
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2 . 小明在做题的时候发现,两个连续正整数的积的倒数可以写成两个式子差的形式.观察下面式子,完成以下问题:
,
,
,…
(1)请写出第15个式子:___________;
(2)请用含
的式子表示第
个式子:___________;
(3)计算:
;
(4)思考:如果不是两个连续正整数的积的倒数又如何去解决呢,请类比上题的方法计算:
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d842b2e150d723c948234ee36f4b6b0c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b61dfa259a7cfab28fe63ff7d6211b1a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a7f4890678dc22224b4d23a8c38fbf11.png)
(1)请写出第15个式子:___________;
(2)请用含
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(3)计算:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7c887eae327ba27f6b065da701f830ec.png)
(4)思考:如果不是两个连续正整数的积的倒数又如何去解决呢,请类比上题的方法计算:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c15a87720211212a15acbd0bc074234e.png)
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2023-01-06更新
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112次组卷
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2卷引用:湖北省十堰市房县2023-2024学年七年级上学期期中数学试题
3 . 如图,把火柴棒按照如图所示的规律排列,其中第1个图形由3根火柴棒组成,第2个图形由5根火柴棒组成,第3个图形由7根火柴棒组成,……,按照此规律,第
个图形中火柴棒的根数为___________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb80913fc086c6a264ed476d193e7344.png)
![](https://img.xkw.com/dksih/QBM/2022/11/7/3104724085932032/3147189897846784/STEM/34a54ad9a7c24cf79fdcce85f320d686.png?resizew=303)
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2023-01-06更新
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62次组卷
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3卷引用:湖北省十堰市房县2023-2024学年七年级上学期期中数学试题
4 . 在七年级数学学习中,常用到分类讨论的数学方法,以化简
为例.当
时,
;当
时,
;当
时,
.求解下列问题:
(1)当
时,
值为______,当
时,
的值为______,当
为不等于0的有理数时,
的值为______;
(2)已知
,
,求
的值;
(3)已知:
,
,…,
,
,这2022个数都是不等于0的有理数,若这2022个数中有
个正数,
,则
的值为______(请用含
的式子表示)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5dc51e97939a8966daa015535a801561.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/08115d6d9f876dea921a4d32260ff1fb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/af0c688a4c1c62abcccabaa750dd31e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb45f673c56a289ea78831c9237e8d20.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb9b24a197fba2aeae456a8be748ba70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e541ea2f855f981c96207070683d388.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ae1f149aa469f85c6ebc0a3983e5cce.png)
(1)当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e55aa0a20848c37c1892c567b2315e04.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e94bdce5b5cb5241a4a56e381d442744.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ba53065eb180a682305fddb95d14b62f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e94bdce5b5cb5241a4a56e381d442744.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e94bdce5b5cb5241a4a56e381d442744.png)
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/010a4454ab3d2c9dd6bfaf3e52162ea5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/162849c3ba37c94f4184db3897a2e243.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8a75f3d81d3d3a2f87a41c4af2f35889.png)
(3)已知:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c814128ea2139e33db94ea590e7c2223.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aec19b68e3add9d5bfcc6269a1855b87.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/11655cca4069cdd8578e1a02711cb049.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9fffeb69f39984ee558427fb1293f943.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb7182c660af83e122483fb0cbc88a6f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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2022-12-02更新
|
143次组卷
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2卷引用:湖北武汉洪山区杨春湖实验学校2023-2024学年七年级上学期月考数学试题
5 . 观察下面有一定规律的三组数:
(1)
,4,
,8,
,…;
(2)
,1,
,5,
,…;
(3)
,
,
,
,
,…;
解答下列问题:
(1)每组的第7个数分别是______,______,______;
(2)第二组和第三组的第
个数分别是______;(用含
的式子来表示)
(3)取每组的第
个数,若这三个数的和为172,求
的值.
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01317332a203c898536b1d0459f51d23.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/32e22e1223baf7cb3d53e668c2449609.png)
(2)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d13ce3ebd1112220c639562739f1f9d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3aab28a20b5bf47040aaec03b1eb550.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/77424dbdd740737b4ec75d62cdd08b27.png)
(3)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f89eef3148f2d4d09379767b4af69132.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/acbc6a613224461ade69362d46550474.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a4b8503f4706b8321e4e79a87eadea84.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/274a9dc37509f01c2606fb3086a46f4f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/533a7b702ada1dd80123e4041271d521.png)
解答下列问题:
(1)每组的第7个数分别是______,______,______;
(2)第二组和第三组的第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(3)取每组的第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0a532e15e232cb4b99a8d4d07c89575.png)
您最近一年使用:0次
2022-12-02更新
|
138次组卷
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2卷引用:湖北省随州市曾都区2023-2024学年七年级上学期期中数学试题
6 . 观察下列图形的规律,依照此规律第10个图形中共有( )个点
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/90d5efc1-7985-4e29-922b-c33c00760c47.png?resizew=310)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/11/29/90d5efc1-7985-4e29-922b-c33c00760c47.png?resizew=310)
A.165 | B.160 | C.145 | D.150 |
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2022-11-27更新
|
97次组卷
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3卷引用:湖北省宜昌市夷陵区樟村坪中小学2023-2024学年七年级上学期期中数学试题
7 . 我国宋代数学家杨辉发现了
(
,1,2,3,…)展开式各项系数的规律:
![](https://img.xkw.com/dksih/QBM/2022/11/17/3111728214335488/3116789225684992/STEM/7179293279154f69bfc94a8de42d2626.png?resizew=550)
以上系数三角表称为“杨辉三角”,根据上述规律,
展开式的系数和是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3f5abcb3802cf02be93a8c89067bd49a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dfd09fb9482124fd35f19b86894648f4.png)
![](https://img.xkw.com/dksih/QBM/2022/11/17/3111728214335488/3116789225684992/STEM/7179293279154f69bfc94a8de42d2626.png?resizew=550)
以上系数三角表称为“杨辉三角”,根据上述规律,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83aeab3328d42f2fd52bbf80d9f0c708.png)
A.64 | B.128 | C.256 | D.512 |
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2022-11-24更新
|
229次组卷
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2卷引用:湖北省武汉市武昌区七校2022-2023学年八年级上学期期中联考数学试题
8 . 观察下列四行数,回答下面的问题:
,...;①
,…;②
,…;③
,...;④
(1)第①行数的第7个数是_____;
(2)设第①行第
个数为
,写出第②行数的第
个数是_____(用含
的式子表示);
(3)取每行数中的第
个数,则第①②④行这三个数的和能否等于
?如果能,请你求出
的值,如果不能,请说明理由;
(4)若第③行连续三个数的和恰为
,直接写出这三个数分别为_____.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1e974baac58eec01149883ab1f51207a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a62422a461e2492abbcc93fb73c708a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3ec32b28761ab0196c1159c33d9d267.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c1eaea471584c01f03ef934652fae89.png)
(1)第①行数的第7个数是_____;
(2)设第①行第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4887473a8091e1ef53a169cc9f211e3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4887473a8091e1ef53a169cc9f211e3a.png)
(3)取每行数中的第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f1859dae0e2e69b60f2c1676ae13c386.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/294f5ba74cdf695fc9a8a8e52f421328.png)
(4)若第③行连续三个数的和恰为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/45aeb674e5eae6278bae8919fe3573fa.png)
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2022-11-24更新
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252次组卷
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6卷引用:湖北省武汉市黄陂区武湖中学2023-2024学年七年级上学期期中数学试题
9 . 如图所示的是中国南宋数学家杨辉在详解《九章算法》中出现的三角形状的数列,又称为“杨辉三角形”该三角形中的数据排列有着一定的规律,若将其中
组斜数列用字母
、
,
,
代替,如图
,则
的值为( )
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/22/d71dccf7-5320-462e-9529-1234bb254983.png?resizew=365)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b700fa9aeb1016aa71f76e4b6bb212e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e72adb45c60c2f63b46e65ff787302bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e88093a749c0d46e0ee931ecfaff925.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/6c1ccc6c74b8754e9bcbb3f39a11b6f1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07096af3b99fd1cb11c31f19a2c6408e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/83f8b6caaf97a4b067c5f9570ce3092a.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/9/22/d71dccf7-5320-462e-9529-1234bb254983.png?resizew=365)
A.![]() | B.![]() | C.![]() | D.![]() |
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2022-09-21更新
|
610次组卷
|
6卷引用:2023年湖北省武汉市经开外国语学校中考一模数学试题
2023年湖北省武汉市经开外国语学校中考一模数学试题安徽省淮南市田家庵区洞山中学2023-2024学年七年级上学期期中模拟数学试题(已下线)浙江省金华市婺城区2023-2024学年九年级上学期期末数学试题 安徽省合肥四十五中橡树湾校区2021-2022学年七年级下学期期中数学试卷 (已下线)【单元测试】第三章 整式及其加减(B卷·能力提升练)-【单元测试】2022-2023学年七年级数学上册分层训练AB卷(北师大版)安徽省芜湖市市区2022-2023学年七年级上学期期中考试数学试题
10 . 在平面直角坐标系中,横坐标、纵坐标都为整数的点称为整点,观察图中每一个正方形(实线)四条边上的整点个数,请你猜想由里向外的第2022个正方形(实线)四条边上的整点共有( )个
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/32a625e3-201d-4abe-9a88-1ca8dd985e29.png?resizew=266)
![](https://img.xkw.com/dksih/QBM/editorImg/2022/8/14/32a625e3-201d-4abe-9a88-1ca8dd985e29.png?resizew=266)
A.8088 | B.8092 | C.6066 | D.6070 |
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