Two important log rules are relevant here (these are important enough to commit to memory because they are essential to manipulating logarithms algebraically -- it would also be useful for you to take some time to understand why these properties are true, as they are fundamental to knowing what a logarithm is):
logb(XY) = logbX + logbY
logb(XY) = YlogbX
These properties generalize to logarithms of any base (e , 10, etc.). The second follows easily from the first. And the 1st follows from the fact that logs are inverse functions of exponentials. With exponents bX·bY= bXY