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

学习 时间:2026-03-30 15:40:14 阅读:6701
如果x2+xy=2,xy+y2=-1,则x2-y2=______,x2+2xy+y2=______.

最佳回答

哭泣的中心

紧张的河马

2026-03-30 15:40:14

(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.

最新回答共有2条回答

  • 风趣的灰狼
    回复
    2026-03-30 15:40:14

    (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.

上一篇 直线和平面垂直

下一篇 would you like to go bike riding with us tomorrow?请问这样以would