How calculate one side limit with WolframAlpha?

Question

I read examples, and try:

lim ln(x+1) as x->inf from the left

but always wolfram alpha represent infinity as positive.

$\ln(x+1)$ doesn't exist in $\mathbb{R}$ for $x\leq -1$. How can you compute limit at $-\infty$? It is not possible — Raffaele, Nov 22 '17 at 10:26
@Raffaele $\ln(x+1)$ does not exist for $x < -1$. The $=$ sign has not to be taken into account. — Enrico M., Nov 22 '17 at 10:28
Could you possibly have $x\to\infty$ from the right? Seems to me like $x\to\infty$ without any direction specifications should work just fine. — Arthur, Nov 22 '17 at 10:33
@HenryTuring What do you mean? As long as I know $\log 0$ doesn't exist even in $\mathbb{C}$... — Raffaele, Nov 22 '17 at 10:39

score 0 · Accepted Answer · answered Nov 22 '17 at 10:26

Just write

Limit of "your function" as $x$ -> $x_0$ (your point) from the left/right

In your case, specify "plus infinity" or $+\infty$. Or minus.

In any case, the $\log$ has no limit for points from the left. It does not exist.

Except all the points $x_0 > -1$, because you have $\ln(x+1)$.

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