如果x2+xy=2,xy+y2=-1,则x2-y2=------,x2+2xy+y2=------.

学习 时间:2026-11-14 05:38:39 阅读:9581
如果x2+xy=2,xy+y2=-1,则x2-y2=______,x2+2xy+y2=______.

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暴躁的溪流

乐观的学姐

2026-11-14 05:38:39

(1)∵x2-y2=x2+xy-xy-y2=x2+xy-(xy+y2)而x2+xy=2,xy+y2=-1,∴x2-y2=2-(-1)=3;(2)∵x2+2xy+y2=x2+xy+xy+y2,而x2+xy=2,xy+y2=1,∴x2+2xy+y2=x2+xy+xy+y2=2-1=1;故答案为:3,1.

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  • 笑点低的手套
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    2026-11-14 05:38:39

    (1)∵x2-y2=x2+xy-xy-y2=x2+xy-(xy+y2)而x2+xy=2,xy+y2=-1,∴x2-y2=2-(-1)=3;(2)∵x2+2xy+y2=x2+xy+xy+y2,而x2+xy=2,xy+y2=1,∴x2+2xy+y2=x2+xy+xy+y2=2-1=1;故答案为:3,1.

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