lgx+lgy = 1 => lgx = 1- lgy => x = 10^(1-lgy) => x = 10/y
2/x + 5/y = y/5 + 5/y ==> y 趋向5,= 2最小值
lgx+lgy=1,则2/x+5/y最小值是?
lgx+lgy = 1 => lgx = 1- lgy => x = 10^(1-lgy) => x = 10/y
2/x + 5/y = y/5 + 5/y ==> y 趋向5,= 2最小值