Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Why books say that is necessary in Legendre equation to have $l$ integer if you want regular solutions in $\vert x\vert \leq 1$. It seems not necessary.

Thanks in advance.

share|cite|improve this question
"It seems not necessary." - what gave you the idea? Both kinds of Legendre functions will necessarily display singularities at $\pm 1$, with the notable exception of the Legendre polynomials (and that bit has a whole lot to do with the integer restriction)... – J. M. Nov 8 '12 at 6:27

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Browse other questions tagged or ask your own question.