已知1/x+1/y=5,求x+2xy+y/2x-3xy+2y的值如题.
问题描述：
已知1/x+1/y=5,求x+2xy+y/2x-3xy+2y的值
如题.
答
1/x + 1/y = 5
(x+y)/x*y = 5
x+y = 5*x*y
x+2xy+y = x+y + 2xy = 5xy+2xy = 7xy
2x-3xy+2y = 10xy-3xy = 7xy
(x+2xy+y)/(2x-3xy+2y) = 1