It depends on the context. can either mean or it can mean , which are twoverydifferent things. I typically use it as the former expression, but there are cases where you would want to use it for the latter.

Edit: By the way, note that the function is ln(x), not Ln(x) or LN(x). Mathematics (and Physics, and Engineering, and...) is a "case-sensitive" field of study.

-Dan