解方程组:(x+y)^2-2xy-(x^2)(y^2),x+y-xy=4解方程组(x+y)^2-2xy-(x^2)(y^2)=10x+y-xy=4

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解方程组:(x+y)^2-2xy-(x^2)(y^2),x+y-xy=4解方程组(x+y)^2-2xy-(x^2)(y^2)=10x+y-xy=4

解方程组:(x+y)^2-2xy-(x^2)(y^2),x+y-xy=4解方程组(x+y)^2-2xy-(x^2)(y^2)=10x+y-xy=4
解方程组:(x+y)^2-2xy-(x^2)(y^2),x+y-xy=4
解方程组
(x+y)^2-2xy-(x^2)(y^2)=10
x+y-xy=4

解方程组:(x+y)^2-2xy-(x^2)(y^2),x+y-xy=4解方程组(x+y)^2-2xy-(x^2)(y^2)=10x+y-xy=4
令a=x+y,b=xy
方程组化为:
a²-2b-b²=10
a-b=4
将a=b+4代入1式:b²+8b+16-2b-b²=10
得b=-1
从而a=3
即x+y=3,xy=-1
因此x,y为方程z²-3z-1=0的两个根
解得z=(3±√13)/2
所以原方程有2组解为:
x=(3+√13)/2,y=(3-√13)/2
x=(3-√13)/2,y=(3+√13)/2