f(x1,x2,x3)=x1x2+2x1x3-x2x3 用配方法化为标准型,求过程
如题所述
因为,二次型中不含平方项
所以,应先作一次坐标变换构造出平方项
过程如下图:
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/78310a55b319ebc4727677688126cffc1e171630?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追问好棒!!我能再问你一道题吗
追答好的,记得采纳啊
追问![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/30adcbef76094b369ae8121ca0cc7cd98c109dcc?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追答![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/95eef01f3a292df5d633c7e4bf315c6035a8734a?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
追问嗯嗯,对对,太谢谢你啦!!
追答不客气,谢谢采纳
^_^
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第1个回答 2021-10-10
简单计算一下即可,答案如图所示
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/b7fd5266d0160924a6a3288bc60735fae7cd349f?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
![](https://video.ask-data.xyz/img.php?b=https://iknow-pic.cdn.bcebos.com/34fae6cd7b899e511b08b08450a7d933c9950d9f?x-bce-process=image%2Fresize%2Cm_lfit%2Cw_600%2Ch_800%2Climit_1%2Fquality%2Cq_85%2Fformat%2Cf_auto)
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