1 . 下列按照一定规律排列一组图形,其中图形①中共有2个小三角形,图形②中共有6个小三角形,图形③中共有11个小三角形,图形④中共有17个小三角形,…….按此规律,图形⑩中共有
个小三角形,这里的
( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
A.87 | B.74 | C.62 | D.53 |
您最近一年使用:0次
2 . 如下图,将图1三边长都是
的三角形沿着它的一边向右平移
得图2,再沿着相同方向向右平移
得图3,若按照这个规律平移,则图5中所有三角形周长的和是______
;图
中所有三角形周长的和是___________
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c78d0ab561d0c9bb9099772c596af8bf.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/048b61a5fb5f420c6d7de88db5bc3aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/048b61a5fb5f420c6d7de88db5bc3aa5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efa9fbcfb9595e2f031aa691db4564b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2ac19e2a797cd0a408316988a63b3755.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9efa9fbcfb9595e2f031aa691db4564b.png)
您最近一年使用:0次
3 . 我国古代数学的许多创新和发展都位居世界前列,如南宋数学家杨辉(约13世纪)所著的《详解九章算法》一书中,用如图的三角形揭示
(n为非负整数)的展开式的项数及各项系数的有关规律,此三角形称为“杨辉三角”.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb3eed4e0751362b9a41db30d8b0d760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6d7835b3630c2cffb3434efbf7a1af6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/375d440fa0c1da0617388f0fc270542c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ceefbef8fc285bf1db6d0527e3f4963.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fce92c8101366cb088847ff1720f16b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f06e7d0b352f43d4b42097b43d8e2c86.png)
…
的展开式中第三项的系数为____________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0034de31c6d9f4412cf54a01160c3573.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bb3eed4e0751362b9a41db30d8b0d760.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f6d7835b3630c2cffb3434efbf7a1af6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/375d440fa0c1da0617388f0fc270542c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ceefbef8fc285bf1db6d0527e3f4963.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fce92c8101366cb088847ff1720f16b3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f06e7d0b352f43d4b42097b43d8e2c86.png)
…
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa1fdf8db64ff5dc5ad07ddf731c7269.png)
您最近一年使用:0次
2024七年级下·全国·专题练习
4 . 如图,在直角坐标系中,第一次将
变换成
,第二次将
变换成
,第三次将
变换成
,已知
,
,
,
;
,
,
,
.
变换成
,则
的坐标是 ,
的坐标是 .
(2)若按(1)找到的规律将
进行了
次变换,得到
,比较每次变换中三角形顶点有何变化,找出规律,推测
的坐标是 ,
的坐标是 .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/866b81a8384cce4f24867baca2e6820c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/beb99c20237aca8ff2ba640c28fbc5b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/beb99c20237aca8ff2ba640c28fbc5b2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ef3e5e30a5d97b80edfa260b43c3e02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ef3e5e30a5d97b80edfa260b43c3e02.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d24434eb8bf365cb3145a89771ff95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f71a512987761644b8d7fac755fd89c0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4d104ab5ca1f4839f522e224f6cf0ebb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/98588e87c23e3457b2601e8e9e3a9584.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2694a3c4b93cb6b142692eca80a4bb76.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1f605a7fc2f1064fe14882ee426839db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7a4b7e01e33e0b7a93c9ea2dc23f0d2a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9ee65ee129ab0db9f84b085b01a94937.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0cebca5a278cfdc35447cbc58cfa001d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/67d24434eb8bf365cb3145a89771ff95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0d5bb157a604f1da055ad90bd91ac234.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9e47cd514b2920609e3781c87df6ab70.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a821e643d5fae24caed0faa6d423dad6.png)
(2)若按(1)找到的规律将
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3fe95f656b98b53f71a9d72bf0c9a4b9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c75e563a1219cc5b71503a618ecfb7d8.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d3cfeacc29e6a61c5b3b4e439c0a91df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63f5c583c98a1fd516c6ceaa60b55dec.png)
您最近一年使用:0次
5 . 如图,在平面直角坐标系
中,
,
,
,
是边长为1个单位长度的小正方形的顶点,开始时,顶点
,
依次放在点
,
的位置,然后向右滚动,第1次滚动使点
落在点
的位置,第2次滚动使点
落在点
的位置,…,按此规律滚动下去,则第2025次滚动后,顶点
的坐标是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ee31829d0d4d5f779a957d7df8058ab.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/c5db41a1f31d6baee7c69990811edb9f.png)
![](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/ff32d26c8d44f5fb4813a19c1030a9f5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4c0573e2af8a0dc8c6a1c0af067a324f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c5db41a1f31d6baee7c69990811edb9f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cb442fb1fe1a5d9768cf11c3e1b7ec5b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8455657dde27aabe6adb7b188e031c11.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7cfa2a6d9749a619edf80bad8b3e4962.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次
6 . 乙炔
是最重要的一种炔烃,在工业中可用以照明、焊接及切断金属(氧炔焰),炔烃属于有机化合物,简单的炔烃化合物有乙炔
、丙炔
、丁炔
、戊炔
,…,按照此规律,设一个炔烃分子的碳原子
个数为
(
),请用
表示炔烃分子的氢原子
个数是______ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34c23aaf94cac4e27edd27e6dc718c41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/34c23aaf94cac4e27edd27e6dc718c41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a1d480ecd8ce897ea26d920984db0fd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7be9ee948b86040c6abbccf49e47473.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4b4a263b2791cf4bec5aa70a375c67c2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/db5d2e85c02a030b0eeba5a366686256.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0704f453b2de48d36911f7db496bbf82.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5b8201de1621b4b5bd752a555ef2bf33.png)
您最近一年使用:0次
7 . 观察下列方程组:①
;②
;③
;…若第④方程组满足上述方程组的数字规律,则第④方程组为__________ .
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/746c72c800897d060fad695bc1e3a6df.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1fde4f7f1500456d13ca12418251983e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/272da1c6de189c820145e5d95ce01aba.png)
您最近一年使用:0次
8 . 观察下列等式,解答问题.
;
;
;
…
(1)请直接写出第5个等式: ;
(2)利用上述规律,比较
与
的大小;
(3)直接写出
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/84f8486603d3f472cd3998c1f2d53eb4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8164b7483fb50871ac417e371c3c9d46.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8611c9dcc5c6092cd7e8522472888278.png)
…
(1)请直接写出第5个等式: ;
(2)利用上述规律,比较
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/01de824ecc30e0e06f88bd12b045b7db.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/148bbb64339fc5e504ec52fe1ba4bb8e.png)
(3)直接写出
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/49c00ca246c88bce442e1220f42a55df.png)
您最近一年使用:0次
9 . 观察下列运算:
①由
,得
;
②由
,得
;
③由
,得
.
(1)通过观察,将你发现的规律用含有
的式子表示出来,并注明
的取值;
(2)利用你发现的计算
.
①由
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/916801280e639ddc0700afba2adfe28d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/46916ae4936e634cd05abc59f5a6246e.png)
②由
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/63d8e46976fa60bacb93dca7af921bf6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c64e7bdb41d097a271b68f9ede41c7bc.png)
③由
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ed79024949e5704ca4f71aebb0934464.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cdd10d410047ebef943410ff67882cad.png)
(1)通过观察,将你发现的规律用含有
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)利用你发现的计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c32f7b7d6bbb1ce8f2e7df367c64dd5d.png)
您最近一年使用:0次
2024七年级下·北京·专题练习
10 . 如图,在平面直角坐标系中,已知点
,
,
,
,把一条长为2023个单位长度且没有弹性的细线(线的粗细忽略不计)的一端固定在点
处,并按
的规律紧绕在四边形
的边上,则细线另一端所在位置的坐标是( )
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a26e951d6d2369e8da79a793a93a66a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3e87b3d349194312a934fced615e563c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/183c7f569272c44e2e4ab0f41b4aa1dd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1667f72a6649e27592a21e8bedb0babe.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5963abe8f421bd99a2aaa94831a951e9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/03cc7d04b130693391de95ecedc217e4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/411b38a18046fea8e9fab1f9f9b80a5f.png)
A.![]() | B.![]() | C.![]() | D.![]() |
您最近一年使用:0次