Originally Posted by

**kuntah** yes thanks but,

The problem I had to solve was to prove exp(log(x)=x

So I don't know actually yet, according to the exercise, that this is true

But I know the derivatives of exp and log, and I know there values in 0 and 1. So I use this:

Now if i take the derivative of exp(log(x)), I get exp(log(x))*1/x

This must be equal to 1 then. Then exp(log(x)) must be x, because then

exp(log(x))/x=1, but I can't use this, because this is what I have to prove

Can't I use something else?

Thanks