1. ## Quick limit question

In a lot of questions there is, $\displaystyle \lim_{x \to 0^{+}}$.

I know this means as $\displaystyle x$ tends towards zero positive, but I can't remember whether this means $\displaystyle x$ is going from $\displaystyle +\infty \to 0$ or from $\displaystyle -\infty \to 0$?

2. Originally Posted by craig
In a lot of questions there is, $\displaystyle \lim_{x \to 0^{+}}$.

I know this means as $\displaystyle x$ tends towards zero positive, but I can't remember whether this means $\displaystyle x$ is going from $\displaystyle +\infty \to 0$ or from $\displaystyle -\infty \to 0$?

It's the first one. As x appoaches 'from the right'. I suppose that doesn't actually mean from $\displaystyle +\infty$ rather just from somewhere at the right of $\displaystyle x$ (after all they may be asymptotes and what not to the right of $\displaystyle x$ so if we approached from $\displaystyle +\infty$ we would hit those first!)
It's the first one. As x appoaches 'from the right'. I suppose that doesn't actually mean from $\displaystyle +\infty$ rather just from somewhere at the right of $\displaystyle x$ (after all they may be asymptotes and what not to the right of $\displaystyle x$ so if we approached from $\displaystyle +\infty$ we would hit those first!)