# In a paper says that the limit when $$\alpha \to 0$$ with $$1. Aug 14, 2011 ### alejandrito29 In a paper says that the limit when [tex]\alpha \to 0$$ with $$\sigma = \pm 1$$ of:

$$\frac{1}{4 \alpha}(1 + \sigma \sqrt{1 - \frac{8}{l^2} \alpha } )$$

has a well defined limit only when $$\sigma = - 1$$,

¿why???????...I don't understand

2. Aug 14, 2011

### disregardthat

Re: limit

Well, calculate the limit for sigma = -1, and see what happens when sigma = 1 (try to calculate it).