正数x、y满足正数x、y满足x2—y2=2xy, 求(x—y)/(x y)的值其中x2—y2中的2表示上标,即平方,“/ ”代表分数线

热心网友

正数x、y满足正数x、y满足x2—y2=2xy,x2—y2=2xyx2-2xy+y2-2y2=0(x-y)2=2y2x-y=√2*yx=(√2+1)y(x—y)/(x y)==√2*y/(√2+2)y=√2/(√2+2)=√2(2-√2)/(4-2)=√2-1

热心网友

完全正确!