Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. Join them; it only takes a minute:

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

Let $u$ be an Harmonic function in $B(0,a)$ in $R^3$

we define $I(x)=x\dfrac{a^2}{|x|^2} $

Let $w(x) = u(I(x))$.

Is there a way to prove that $w$ is harmonic without making too much computation?

If not I will make them my self. Thanks for your help!

share|cite|improve this question
up vote 0 down vote accepted

In fact this are call Kelvin transform, and it work In $R^2$ but it needs a modification for $R^3$

share|cite|improve this answer

Your Answer


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

Not the answer you're looking for? Browse other questions tagged or ask your own question.