Question

What is the limit as `x` approaches infinity of `lnx`?

Answer 1

First of all it is important to say that `oo`, without any sign in front of, would be interpreted as both, and it is a mistake!

The argument of a logarithmic function has to be positive, so the domain of the function `y=lnx` is `(0,+oo)`.

So:

`lim_(xrarr+oo)lnx=+oo`, as shown by the graphic.

graph{lnx [-10, 10, -5, 5]}