Talk:Biharmonic equation

Isn't the biharmonic the Laplacian of the Laplacian? In particular... shouldn't there be crossterms???

Fixed it. -Ryan

Shouldn't it be "Any harmonic function is biharmonic..." rather than "Any biharmonic function is harmonic..."? Consider f(x) = x^3. But then don't harmonic functions only need to be twice differentiable? I guess there's a regularity theorem that says that harmonic functions are automatically infinitely differentiable, so harmonic implies biharmonic.

polar vs spherical
Shouldn't it say spherical coordinates instead of polar? --kupirijo (talk) 10:53, 23 September 2010 (UTC)
 * I see now. It is the font of $$\phi$$ that has to change. --kupirijo (talk) 10:56, 23 September 2010 (UTC)