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Simple question:

If I have $\lim_{x \to -3^-}f{(x)}$ and I'm looking at a graph, am I approching -3 from the direction of +$\infty$ to -3 (as in going in the negative direction)? Or am I approaching -3 from the direction of -$\infty$ (as in the positive direction)?

edit: sorry corrected my mistake in the question.

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    @Zev: Me too! That's why I put related and not duplicate.2011-06-13

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"$\displaystyle\lim_{x\rightarrow-3^{-}}$" denotes approaching $-3$ from the left (i.e. from $-\infty$), to the right (i.e. in the positive direction). The Wikipedia page on one-sided limits helps clear things up a bit.

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    Ok, thanks, that hel$p$ed a lot :).2011-06-13
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If you find the $\lim_{x\to -3-} f(x)$ notation confusing, you can also write $\lim_{x\uparrow -3} f(x)$ and think, "this is the limit of $f(x)$ as $x$ increases toward $-3$." Likewise, you can use $\lim_{x\downarrow-3} f(x)$ to denote the right-hand limit.

I readily concede that is a matter of taste, but matters of taste such as this one affect readability, and that's important.