【阅读】我们将
与
称为一对“对偶式”,
因为
,所以构造“对偶式”,再将其相乘可以有效地将
和
中的“
”去掉,于是二次根式的除法可以这样计算:如![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c78d9b11fb443069fb7e09ea86822ce.png)
.像这样,通过分子、分母同乘一个式子把分母中的根号化去,叫做分母有理化.
根据以上材料,理解并运用材料提供的方法,解答下列问题:
(1)对偶式
与
之间的关系是____________;
A.互为相反数 B.绝对值相等 C.互为倒数
(2)已知
,
,化简
,
;
(3)解方程:
.
[提示:令
,
].
(4)求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0a989c4fbf0ff34cedb365d2dda47f16.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/175d0c99e866f1db915462a91b356ef3.png)
因为
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50036f42d68bcb48ee54bf6a8e76856f.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c9928ba39cdd5878aced506d3dbb9fb9.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9b87033f1efe85e559a9a3efc985be9d.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/7aa0dba76fbef65983ebf043218ea5e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/9c78d9b11fb443069fb7e09ea86822ce.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3755d7e08b98c26303f2f61de7e7ddd2.png)
根据以上材料,理解并运用材料提供的方法,解答下列问题:
(1)对偶式
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab46ea0cba2d06283fae3d864a2329e0.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/47cfe4e08c06bde245e58aa22485044c.png)
A.互为相反数 B.绝对值相等 C.互为倒数
(2)已知
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/69e4636f3b6eb54711c4410fa831f623.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/add3e1ba560da4c0904e016eb85940b6.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/81dea63b8ce3e51adf66cf7b9982a248.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d053b14c8588eee2acbbe44fc37a6886.png)
(3)解方程:
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e7e95857b9fcde7b45e59ef3d498e456.png)
[提示:令
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ab49c882cfe6fc298a74b8dbfa5cd815.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/50036f42d68bcb48ee54bf6a8e76856f.png)
(4)求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/e75fd7e405a9928ae2642a15050b1446.png)
更新时间:2024-04-03 08:23:12
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【推荐1】阅读下列材料,然后回答问题.在进行二次根式的化简与运算时,我们有时会碰上如
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/dff38920a512ac5fa9dff5aa52be662a.png)
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![](https://staticzujuan.xkw.com/quesimg/Upload/formula/ea9e515ad2d1c88f318debe6a75c296b.png)
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