Question 1094566
could you please help me evaluate this expression 
log(base 3) (12) - log(base3) (28) + log(base3) (63) 

I'm usually pretty good at these types of questions but my answer bing 4.5 was wrong
<pre>{{{log (3, 12) - log (3, 28) + log (3, 63)}}}
{{{log (3, 12) - (log (3, 28) - log (3, 63))}}}
{{{log (3, 12) - log3 (28/63)}}}
{{{log (3, (12/(28/63)))}}} ====> {{{log (3, 12 * (63/28))}}} =====> {{{log (3, 12 * (9cross(63)/4cross(28)))}}} =====> {{{log (3, 3cross(12) * (9/cross(4)))}}} =====> {{{highlight_green(matrix(1,3, log (3, 27), "=", highlight(3)))}}}
As seen, you don't need a calculator to do this simplification, and you certainly don't have to apply change of base. 
Some people don't even know what change of base is. Chances are, you don't either, but even if you do, you don't need to apply that here.