Log of e raised to an exponent I have a textbook which states the following:
$y=e^{(-\lambda x)}$
it then takes the log of both sides and comes up with:
$log \ y = - \lambda x$
Why is the right side what it is? Shouldn't it be:
$log \ y = (- \lambda x)(log \ e)$
?

After reading the comments, I realized that the textbook is referring to $log_e$ and not $log_{10}$ which is what I have thought my entire life.
