(x+y)×(x-y)+(x-y)的平方-(x平方-3xy)等于多少,大哥大姐帮帮忙啊
答案:3 悬赏:40
解决时间 2021-03-02 17:55
- 提问者网友:暖心后
- 2021-03-02 11:58
(x+y)×(x-y)+(x-y)的平方-(x平方-3xy)等于多少,大哥大姐帮帮忙啊
最佳答案
- 二级知识专家网友:狠傷凤凰
- 2021-03-02 12:03
(x+y)(x-y)+(x-y)²-(x²-3xy)
=(x-y)[(x+y)+(x-y)]-x(x-3y)
=2x(x-y)-x(x-3y)
=x[2(x-y)-(x-3y)]
=x(x+y)
=(x-y)[(x+y)+(x-y)]-x(x-3y)
=2x(x-y)-x(x-3y)
=x[2(x-y)-(x-3y)]
=x(x+y)
全部回答
- 1楼网友:兮沫♡晨曦
- 2021-03-02 14:54
由于2x^2-2y^2=3xy
即有2x^2-3xy-2y^2=0
2 1
1 -2
所以(2x+y)(x-2y)=0
即x=-y/2或者x=2y
当x=-y/2时
(x-y)分之(x+2y)=(-y/2+2y)/(-y/2-y)=-1
当x=2y时
(x-y)分之(x+2y)=(2y+2y)/(2y-y)=4
- 2楼网友:走,耍流氓去
- 2021-03-02 13:18
(x+y)(x-y)+(x-y)"-(x"-3xy)=(x-y)[(x+y)+(x-y)]-x(x-3y)=2x(x-y)-x(x-3y)=x"-xy("是平方)
我要举报
如以上问答内容为低俗、色情、不良、暴力、侵权、涉及违法等信息,可以点下面链接进行举报!
大家都在看
推荐资讯