先化简,再求值:
,其中
,
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/b53c8f0416fde028204f62b6ab8c2d05.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b384412acba251d87902ab928902f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/107babba45f110012183dc4dc54490f7.png)
更新时间:2024-01-22 21:29:17
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相似题推荐
解答题-计算题
|
较易
(0.85)
名校
【推荐1】小明在化简代数式
时出现了错误,他的解答步骤如下:
原式
(第一步)
(第二步)
(第三步)
(1)小明的解答过程是从第_____步开始出错的;
(2)写出正确的解答过程,再求出当
时代数式的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad6377af363251fc45b545f56654a58c.png)
原式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/662de108d6f8ab9e644335175a14071d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2294d129aaa8e2c6b9c93098e7d20b77.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3d5eefd2a1a81c67585f9f62a41fa7cb.png)
(1)小明的解答过程是从第_____步开始出错的;
(2)写出正确的解答过程,再求出当
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/1c98a7f3a8bf384b1dfc1d34aebd46d2.png)
您最近一年使用:0次
解答题-计算题
|
较易
(0.85)
【推荐2】阅读下列材料,解答提出的问题:
原题:已知
求
的值.佳佳先将
利用完全平方公式转化为:![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9241ff451d9b0bb6d4e5fd8f87d21ced.png)
∵
∴
,
,∴原式![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b91b4720c7142a1812b9a0c2b160c01.png)
(1)若
求:
的值;
(2)若
求:
的值.
原题:已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5f4f90af3e09b9801490605f5303376e.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ff05920f9ef5a8939df31eb07fd55110.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d354bf0b4a936d3e429c3c9572c18ead.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9241ff451d9b0bb6d4e5fd8f87d21ced.png)
∵
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3ff5bfc71a1d4cea7432bec5a69df8d1.png)
∴
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5d42e55144e69a8e1a902a215b49bc2d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7332f64a654e4c7834cae87e48d47c41.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/2b91b4720c7142a1812b9a0c2b160c01.png)
(1)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cbc1c43de4c2cf946ffdc2083358f269.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3cbb2e11765d2f289280b77030af02e.png)
(2)若
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/fdf3ff94587d658d5157c4469197d884.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/27e1c70f41e8e1e07d6e41cbe834aad7.png)
您最近一年使用:0次