Editing Dirichlet boundary condition (section)

===PDE===

For a [[partial differential equation]], for example, <math display="block">\nabla^2 y + y = 0,</math> where <math>\nabla^2</math> denotes the [[Laplace operator]], the Dirichlet boundary conditions on a domain {{math|Ω ⊂ '''R'''<sup>''n''</sup>}} take the form
<math display="block">y(x) = f(x) \quad \forall x \in \partial\Omega,</math>
where {{mvar|f}} is a known [[function (mathematics)|function]] defined on the boundary {{math|∂Ω}}.