Hi,

Can someone please explain to me why when solving for $2\ln{x} + \ln{x+2} - \ln{x^2 + 2x} = -\ln{2}$ the solutions for x are 0, 1/2, and -2,but when you substitute these values back into the equation, only x = 1/2 works?

There may be some elementary concept relating to systems of equations that I am missing here, and so I would really appreciate some help!