已知x1是方程x lgx=2005的根，x2是方程x10^x=2005的根，x1x2的值為答案2005

熱心網友

x1*lgx1 = 2005 ...(1), x2*10^x2 = 2005 ...(2)顯然: x1 = 10^x2, x2 = lgx1(1)*(2): x1*x2*lgx1*10^x2 = 2005^2 = x1*x2*x2*x1== x1*x2 = 2005, (x1*x2 0)