(1)计算:
;
(2)先化简,再求值:
,其中
.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ad1a9c49c969f2fab571fa55ac82a6c0.png)
(2)先化简,再求值:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ca99fe1b0681f0d08c69c3f2e3d5661b.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/707ea658f3a9359f5740d5aab48f7948.png)
更新时间:2022-08-04 16:11:33
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