An indeterminate difference
is a limit of $f(x)-g(x)$ where both
$f(x)$ and $g(x)$ are going to $\infty$ (or both are going to
$-\infty$).
DO: The limit of
$f(x)-g(x)$ that looks like $\infty+\infty$ is not
indeterminate. Why not?
The following video shows how to manipulate indeterminate
differences to make them look like indeterminate
quotients, which we can then tackle with L'Hospital's rule.