I'm unsure as to if I am using the correct terminology, but what I mean by this is log = logarithm in base 10. ln = logarithm in base e. logx = logarithm in base x. Upon some investigation, I found that log(a)/ln(a)=log(b)/ln(b) where a and b are constants, meaning that there is a ratio between the logarithms. What is the function of this ratio, in terms of logx and logy? I.e. If logy(c)=f(x)logx(c), what is f(x)? The reason behind my search here is to find out how to put a logx (logarithm in base x) function in terms of ln. I want to experiment with various functions in logx on my graphics calculator, but it doesn't have the option to use logarithms in bases other than e and 10.