1. ## negative logs

"Explain why it is not possible to use the product law of logarithms to evaluate the expression log(-7) + log(-4)?"

I had a TIPS/Comm assignment yesterday, and i had this question. I didn't know how to answer it, except that you can't evaluate xlog(y) with y < 0 .. how would you guys do it?

2. well this isn't a formal proof but...
$
y = log_{a}(x)\$
means $\ x = a^y$

so if $a$ is taken to a postive or negatve exponent $x$ will always be positive

example

$2^3 = 8\ \ 2^{-3} = .1250$