DEigenvalues

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

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

Examples

Find eigenvalues of a differential operator:

DEigenvalues[-Laplacian[u[x, y], {x, y}], u, {x, y} ∈ Disk[], 5]

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