1 . 一个圆形蛋糕放在桌子上用刀切下去,一刀可以切成两块,两刀最多可以切成
块,三刀最多可以切成
块,
刀最多可以切成
块(如图).
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/2/78c9e200-221e-4786-be7f-76953aadd70a.png?resizew=303)
将上述问题转化为数学模型,实际上就是n条直线最多把平面分成几块问题,请先观察下列表格中实验数据,然后解答问题.
(1)求当
时,分成最多的平面块数
的值.
(2)设
条直线把平面最多分成的块数是
,请直接写出
关于
的表达式(
是正整数).
(3)根据(2)中
关于
的表达式,求当
时,
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b06e95b57b7a81cd81d05557a11fa92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c79c562343bd2362a979662d3865020c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2024/1/2/78c9e200-221e-4786-be7f-76953aadd70a.png?resizew=303)
将上述问题转化为数学模型,实际上就是n条直线最多把平面分成几块问题,请先观察下列表格中实验数据,然后解答问题.
直线条数n | 1 | 2 | 3 | 4 | … |
分成的最多平面块数 | 2 | 4 | 7 | 11 | … |
(1)求当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/489fba06ac8e6e770b67c375e7554463.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d27182444d3da4003680f07ec299087c.png)
(2)设
![](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/08eb71ecf8d733b6932f4680874dbbf3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(3)根据(2)中
![](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/ece00d26c3767fc91e2eaf9ff5e2ad7a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b87df689b605e7a283b56d454c3736a0.png)
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名校
2 . 观察下面的三行单项式.
x、
、
、
、
、
、……①
、
、
、
、
、
、……②
、
、
、
、
、
、……③
(1)根据你发现的规律,第①行第7个单项式为______;
(2)第②行第8个单项式为_______;第③行第8个单项式为_______;
(3)取每行的第11个单项式,令这三个单项式的和为A,计算当
,
的值.
x、
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2564899e9403e844ca5fcc5aa82a61cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d4390b0dc2336273b82abed3ef4bc50b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3c88722ed9bb974f09bde7cf88783f96.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/113802e862407d87077eaf61e5b8be94.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/604c010c73a46349090fcc356b3e09a4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f0e71978def5c27b89988665648a2d90.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5c0e17b63a75587ae79fe51e29b44d3a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/255031490db9d5dfc181ad9ed39437d6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a9aa5e2eaba16e345cbb911293926a98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/256f679287555013e2085a98e64072bd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/de451b9f2b0d9ccd8f43944f724f1484.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2564899e9403e844ca5fcc5aa82a61cd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4acb8b1d533e1749b072eba0150676bb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fe2fcbd722f1693726bb647f0acf21d0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/923b0500b0da82b64cea8dc355ed6b6c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a46385f6ea2e162c682344e3bc082900.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e3e47a430f564d9c1cb515e7bcc00e12.png)
(1)根据你发现的规律,第①行第7个单项式为______;
(2)第②行第8个单项式为_______;第③行第8个单项式为_______;
(3)取每行的第11个单项式,令这三个单项式的和为A,计算当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b650820d7bed48ed67a2869ad8c65ff1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f56f8835c1c3c309ee770a684ee9fe5.png)
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3 . 将正整数1至2023按照从左到右的顺序填入下面表格中:
规定:
表示第m行第n个数,如
表示第3行第2个数是20,记作
.
(1)
______;
(2)若
,则
______,
______;
(3)将表格中的“T”型格子看成一个整体并可以平移,所覆盖的4个数之和能否等于113?如果能,求出4个数中的最小数;如果不能,请说明理由;
(4)用含m、n的代表表示
______.
1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 |
10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 |
19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 |
… |
规定:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7ff1f31ff1a97ec4907609992df726f0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2c2284f4d6ecb00ba049df932473ad0e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a1420a8aa80af6584bd435691c4cb7a0.png)
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa089a22e818f1ea4389eacfbfc03db1.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d90b85b696ea6b418e14e9544b2b821f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a6c57bbef89a37f1a3808c0ceeac0c22.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f3cb8d72bb2e281b943b3b430138ef7.png)
(3)将表格中的“T”型格子看成一个整体并可以平移,所覆盖的4个数之和能否等于113?如果能,求出4个数中的最小数;如果不能,请说明理由;
(4)用含m、n的代表表示
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/da9fb8cfacbd0eea27aef997f02b6e8d.png)
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4 . 把正奇数
,
,
,
,
排成如图所示的
列,规定从上到下依次为第
行,第
行,第
行,
,从左到右依次为第
列至第
列.回答如下问题:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/27/35dcf5b8-592b-49b9-9860-89aa60239588.png?resizew=227)
(1)①图表中第
列第
行的数为_____;
②图表中第
行第
列的数可表示为_____.(用含有
的代数式表示,要求化为最简形式)
(2)按如图所示的方法用一个“
”形框框住相邻的三个数,设被框的三个数中,最小的一个数为
,是否存在这样的
,使得被框的三个的数和等于
?若存在,求出
的值,若不存在,请说明理由.
(3)若在(2)中“
”形框框住的三个数的和记为“
”,则
的最大值与最小值的差等于_____.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d91e07104b699c4012be2d26160976a2.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f782d70309802445202487eee751cbdd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2030a7c508abe4b2a03bc702cf7692d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b06e95b57b7a81cd81d05557a11fa92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61128ab996360a038e6e64d82fcba004.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5ca7d1107389675d32b56ec097464c14.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f782d70309802445202487eee751cbdd.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b06e95b57b7a81cd81d05557a11fa92.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/27/35dcf5b8-592b-49b9-9860-89aa60239588.png?resizew=227)
(1)①图表中第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b8860d9787671b53b1ab68b3d526f5ca.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d07ae0b4264da6a8812454ffd2f20d94.png)
②图表中第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8b06e95b57b7a81cd81d05557a11fa92.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)按如图所示的方法用一个“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/aa83681a17608a1784ae1df4682f5c98.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
(3)若在(2)中“
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0c88d9142df6ba8e43c1a93bd04a1362.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cf231f8f86fb922df4ca0c87f044cec3.png)
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5 . 观察下列三行数:
①2,4,6,8,…
②
,
,
,
,
,…
③0,5,10,15,20,…
(1)第①行的第9个数是________,第
个数是________;
(2)第②行的第
个数是________,第③行的第
个数是________;(用含n的代数式表示)
(3)如图,用一个长方形方框框住六个数,左右移动方框,框住的六个数之和可以用含n的代数式表示.则当
时,框住的六个数字之和为___________.(直接写出结果即可)
①2,4,6,8,…
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d13ce3ebd1112220c639562739f1f9d1.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8bf3d3564c61e5e9c39a9e2cf2de048b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8eed5ece335b63af168c7c36d2121947.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8f88b597e0729b052743f9d8b7923b28.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/4014daff61e2c227e7a38e4caf3a82e8.png)
③0,5,10,15,20,…
(1)第①行的第9个数是________,第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)第②行的第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(3)如图,用一个长方形方框框住六个数,左右移动方框,框住的六个数之和可以用含n的代数式表示.则当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e4c91fd038f8b7ab27b1913f92d2930c.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/27/c45c4b34-fb90-4352-92a0-ad8f352c563b.png?resizew=252)
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6 . 小明同学在查阅大数学家高斯的资料时,知道了高斯如何求
.小明于是对从
开始连续奇数的和进行了研究,发现如下式子:
第1个等式:
;
第2个等式:
;
第3个等式:
;
探索以上等式的规律,解决下列问题:
(1)
;
(2)完成第n个等式的填空:
;
(3)利用上述结论,计算
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c66d74ddacd376a3936706fabf015fd4.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/bdaa19de263700a15fcf213d64a8cd57.png)
第1个等式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c1db1c8f88c5de20586db0cde44d3e28.png)
第2个等式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/194969148c9c1b7df23d1c65f16767da.png)
第3个等式:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/90c94bed97397edf43702cba40b6aec6.png)
探索以上等式的规律,解决下列问题:
(1)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f26c63ffa335de0a9e54a779bbfa43e5.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/921ef5abce73648e3834140df9a72aa8.png)
(2)完成第n个等式的填空:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9afd853e8215cb0486132e473cf9667.png)
(3)利用上述结论,计算
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c7dd60045dffab291246d697fb8d013c.png)
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7 . 如图所示,它是一个三角点阵,从上向下数有无数多行,其中第一行有1个点,第二行有2个点……,第
行有
个点,……
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/13/ea1836b4-6f58-4a95-9b19-582182ed17fe.png?resizew=172)
(1)第一行有1个点,前两行点数和是3,前三行点数和是6,请问前四行的点数和是 ,前
行的点数和是 ;
(2)探究发现,120是前 行的点数和;
(3)三角点阵中前
行的点数和能是600吗?如果能请求出;如果不能,试用一元二次方程说明理由.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/13/ea1836b4-6f58-4a95-9b19-582182ed17fe.png?resizew=172)
(1)第一行有1个点,前两行点数和是3,前三行点数和是6,请问前四行的点数和是 ,前
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(2)探究发现,120是前 行的点数和;
(3)三角点阵中前
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
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2023-12-25更新
|
61次组卷
|
2卷引用:山东省临沂市兰山区2023-2024学年九年级上学期期中数学试题
8 . 某电影院地面的一部分是扇形,观众席每排的座位数如下表:
按这种方式排下去.
(1)第7排、第8排各有多少个座位?
(2)第
(
,且
为正整数)排有多少个座位?
(3)若某排有110个座位,则该排的排数是多少?
排数 | 1 | 2 | 3 | 4 | 5 | … |
座位数 | 50 | 54 | 58 | 62 | 66 | … |
(1)第7排、第8排各有多少个座位?
(2)第
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e167b43045b3297248e334c41c621b8f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(3)若某排有110个座位,则该排的排数是多少?
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2023-12-24更新
|
17次组卷
|
2卷引用:安徽省芜湖市无为市多校联考2023-2024学年七年级上学期月考数学试题
名校
9 . 观察下列图形,寻找规律,回答下列问题:
定义数列:
、
、
、
、……,其中
,
(k为任意正整数).
以数列中每一项的数为边长画出正方形,再将这些正方形按下图规律依次拼成长方形.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/22/f515b5d6-554b-4a11-9ec0-bc1587fa4f81.png?resizew=394)
(1)按照图中规律,图⑤的长方形的周长为______;
(2)按照图中规律,图⑨的长方形的面积为______;
(3)从图中总结规律:
______.
定义数列:
![](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/daf464629fa321a6ff7401ab79f07083.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/8323901a49cac29afd7d62864f088077.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/affad72429ee4ab8cb49851def9b21a5.png)
以数列中每一项的数为边长画出正方形,再将这些正方形按下图规律依次拼成长方形.
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/22/f515b5d6-554b-4a11-9ec0-bc1587fa4f81.png?resizew=394)
(1)按照图中规律,图⑤的长方形的周长为______;
(2)按照图中规律,图⑨的长方形的面积为______;
(3)从图中总结规律:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7d4c5040235e00c15c6e03957cddedfa.png)
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2023-12-23更新
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119次组卷
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2卷引用:北京师范大学附属实验中学2023-2024学年七年级上学期月考数学试题
10 . 如图是2023年8月的月历:
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/22/ff297d62-0ff7-4340-889a-66f4cef7f8ef.png?resizew=440)
(1)图1和图2在月历中框出4个代表日期的数
,请用一个等式表示a、b、c、d之间的关系;
(2)已知本月框出的4个代表日期的数字之和是88,那么最小的日期对应的是星期几?
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/22/ff297d62-0ff7-4340-889a-66f4cef7f8ef.png?resizew=440)
(1)图1和图2在月历中框出4个代表日期的数
![](https://img.xkw.com/dksih/QBM/editorImg/2023/12/22/5c8a09eb-0110-415e-b39f-402b245677b1.png?resizew=59)
(2)已知本月框出的4个代表日期的数字之和是88,那么最小的日期对应的是星期几?
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