Differential Equations

Which of the following boundary condition types are correctly matched for partial differential equations?

Options:

• (A) Dirichlet boundary condition: Specified value of the unknown function $u$ on the boundary
• (B) Neumann boundary condition: Specified normal derivative $\frac{\partial u}{\partial n}$ on the boundary
• (C) Robin (mixed) boundary condition: Linear combination of $u$ and $\frac{\partial u}{\partial n}$ on the boundary
• (D) Cauchy boundary condition: Both $u$ and its normal derivative specified on the boundary