DEigensystem

DEigensystem[ℒ[u[x,y,…]],u,{x,y,…}∈Ω,n] gives the n smallest magnitude eigenvalues and eigenfunctions for the linear differential operator ℒ over the region Ω.

DEigensystem[eqns,u,t,{x,y,…}∈Ω,n] gives the eigenvalues and eigenfunctions for solutions u of the time-dependent differential equations eqns.

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