先化简,再求值:
,其中
,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e16af69da713ad31c9366d7b2c311dfb.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b384412acba251d87902ab928902f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c50866229ec5a3640fb250f9bd2192b3.png)
更新时间:2023-04-30 15:11:01
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解答题-问答题
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名校
【推荐1】如图,自行车每节链条的长度为
,交叉重叠部分的圆的直径为
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(1)填表:
(2)用含有
的代数式表示
节链条总长;
(3)如果用自行车的链条(安装前)由
节这样的链条组成,求这根链条安装完成后的总长约为多少?(结果精确到
)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b0794c29dd67ce995cb4ac622fb0555c.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e2a27a670a3cf2ea69157d39c8e9c27d.png)
(1)填表:
链条节数 | ![]() | ![]() | ![]() | ![]() | …… |
链条总长(![]() | ![]() | …… |
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b6a24198bd04c29321ae5dc5a28fe421.png)
(3)如果用自行车的链条(安装前)由
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5021dda43ea360fb7b1102c1a462693a.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/048b61a5fb5f420c6d7de88db5bc3aa5.png)
![](https://img.xkw.com/dksih/QBM/2021/11/11/2848830027358208/2854688336322560/STEM/71e16172-3f71-4f44-873c-2bcd4c959943.png)
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解答题-计算题
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较易
(0.85)
【推荐1】先化简,再求值:(x-y)2+(x-y)(x+y),其中x=3,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c2f3fa679bb55ded25a9b72a8e788cb1.png)
您最近一年使用:0次
解答题-计算题
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较易
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【推荐2】(1)化简:
;
(2)若x满足条件
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/28f93991fff95ac570c8f96591ea2d98.png)
(2)若x满足条件
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d7d36d0132b309a865f7141cf9d58f85.png)
您最近一年使用:0次