计算题哈,若代数式x^2+y^2-14x+2y+50的值为0.化简求值:[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]请把每一步写清楚了,

来源:学生作业帮助网 编辑:作业帮 时间:2024/07/04 23:32:14
计算题哈,若代数式x^2+y^2-14x+2y+50的值为0.化简求值:[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]请把每一步写清楚了,
x͑J@_cB$>Hi@@^[QU*x!e2+86B$x2;,# f4~GN^g*QlAum9%Q,oulTWL8[px& u F԰TY8. {I҉mF%q[uT)ab&Y/M:K*"tG7x,rYʶ^(VYҋZk>nēJUe p4gЧ0[xaWI4+bx8^}#_Z

计算题哈,若代数式x^2+y^2-14x+2y+50的值为0.化简求值:[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]请把每一步写清楚了,
计算题哈,
若代数式x^2+y^2-14x+2y+50的值为0.
化简求值:[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]
请把每一步写清楚了,

计算题哈,若代数式x^2+y^2-14x+2y+50的值为0.化简求值:[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]请把每一步写清楚了,
如果使代数式x^2+y^2-14x+2y+50的值为0,则
x^2+y^2-14x+2y+50=0
(x-7)^2+(y+1)^2=0
x=7,y=-1
[2x^2-(x+y)(x-y)]-[(-x-y)(-x+y)+2y^2]
=[2x^2-(x^2-y^2)]-[(x^2-y^2)+2y^2]
=(x^2+y^2)-(x^2+y^2)
=x^2+y^2-x^2-y^2
=0
(好像不应该是这样的呀,原题目中哪儿搞错了?)