已知
,
,求
的值.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/5625362801135034fa4da513fc2ffdee.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/36e5c4a25a1616e1592aec16f44bca95.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/831d516adaa8d5c2549c449d96882b1c.png)
更新时间:2023-07-09 19:33:45
|
相似题推荐
解答题-问答题
|
适中
(0.65)
【推荐1】完全平方公式:
适当的变形,可以解决很多的数学问题.
![](https://img.xkw.com/dksih/QBM/2022/1/6/2894321181573120/2952300270018560/STEM/d10316ab-ebf9-4d5d-92db-dcbccdd18f81.png?resizew=157)
例如:若a+b=3,ab=1,求
的值.
解:因为a+b=3,ab=1,所以
,2ab=2,![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89ed2b89014d649606d0b1bf5ba06b0a.png)
即可得得
根据上面的解题思路与方法,解决下列问题:
(1)若x+y=8,
,则xy=______;
(2)①若2a+b=5,ab=2,求2a-b的值;
②若(4-x)(5-x)=8,求
的值;
(3)如图,点C是线段AB上的一点,以AC,BC为边向两边作正方形的,设AB=6,两正方形的面积和
,求图中阴影部分面积.
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/07e9827b352d32a5e7d67eafab43da11.png)
![](https://img.xkw.com/dksih/QBM/2022/1/6/2894321181573120/2952300270018560/STEM/d10316ab-ebf9-4d5d-92db-dcbccdd18f81.png?resizew=157)
例如:若a+b=3,ab=1,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/c925be255ca736a53b24d13ddede1a86.png)
解:因为a+b=3,ab=1,所以
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/cccf55336a61ee88a074afa0557a4a51.png)
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/89ed2b89014d649606d0b1bf5ba06b0a.png)
即可得得
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/eb6c334918a51cb6909f85bf1b71a95f.png)
(1)若x+y=8,
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f2f507eda00fc660a1eee85681999d67.png)
(2)①若2a+b=5,ab=2,求2a-b的值;
②若(4-x)(5-x)=8,求
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/3a9a07b7a7c88f4eea78e00526a66790.png)
(3)如图,点C是线段AB上的一点,以AC,BC为边向两边作正方形的,设AB=6,两正方形的面积和
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/61e685a26529ce6133410cb40cff6a38.png)
您最近一年使用:0次
解答题-问答题
|
适中
(0.65)
【推荐2】以下四个式子的变形中,正确的有哪些?错误的有哪些?如若错误,请写出正确的答案.
①
;
②
;
③
;
④
.
①
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f13b768ca5d2db6371ba763c2f7a9c7b.png)
②
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/d2e885bea5174a3f306d2844128b621f.png)
③
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/0f0c397bfc119770efa2a592e3993fad.png)
④
![](https://staticzujuan.xkw.com/quesimg/Upload/formula/f3aa48a6349eddaaaeaa2d25c53356e1.png)
您最近一年使用:0次