观察下列等式:
,
,
,
将以上三个等式两边分别相加得:
.
(1)猜想并写出:
.
(2)直接写出下列各式的计算结果:
①
;
②
.
(3)探究并解决问题:
如果有理数a,b满足∣ab-2∣+∣1-b∣=0,试求:
的值.
![](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)
将以上三个等式两边分别相加得:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/803b4243a314353ccc0e2b7ea67bafcb.png)
(1)猜想并写出:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/a0238657619e3f3b63c0affd5d3b7492.png)
(2)直接写出下列各式的计算结果:
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b7e9be111c42b915d35cbe481ff92e29.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7b9347c2a36c0a07093a9d2397fb7ab8.png)
(3)探究并解决问题:
如果有理数a,b满足∣ab-2∣+∣1-b∣=0,试求:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27f2873c66f38c010a03314ad8cd215c.png)
20-21七年级上·湖北黄冈·阶段练习 查看更多[3]
湖北省麻城思源实验学校2020-2021学年七年级上学期9月月考数学试题(已下线)期中复习(高频考点精选50题特训)-2023-2024学年七年级数学上学期期中期末考点归纳满分攻略讲练(北师大版)甘肃省平凉市庄浪县2023-2024学年七年级上学期期中数学试题
更新时间:2020-10-06 23:03:56
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【推荐2】探索规律.
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(1)观察上面的各图形,我们会发现:
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