Log Rule #1: log(x*y) = log(x)+log(y)
Log Rule #2: log(x^y) = y*log(x)
Using those log rules, we can say...
3*log(2) + log(4) = log(2^3) + log(4) <-- use log rule #2
3*log(2) + log(4) = log(8) + log(4) <-- simplify 2^3 to get 8
3*log(2) + log(4) = log(8*4) <-- use log rule #1
3*log(2) + log(4) = log(32) <-- simplify 8*4 to get 32
So the expression simplifies to log(32)