The Log function!!

I calculators you can't change or set the base of 'log' is default 10 so you need to know these:

log x (base y) = log x / log y

when log x it's automatic log x (base 10) here some examples:

log 8 (base 2) = log 8 / log 2
log 27 (base 3) = log 27 / log 3

and the base it's default 10 again, and that is how you need to use it in calculators(no bases), and here the explanation to this:

log x (base y) = log x (base 10) / log y (base 10) = (log x / log 10) / (log y / log 10) = (log x / log 10) * (log 10 / log y) = log x / log y

here so other stuff about 'log' :

log (x*y) = log x + log y
log (x/y) = log x - log y

Hope it's helped ☺