线性算符L 方程类型方程线性算符L 波动方程 a-u_02v2u=f L= 02 02 at 热传导方程 0u_2 0 at at Poisson方程V2a=f L≡ 线性性质:a+a2=a]+a2l](
Main Properties of Linear PDE’s Wave Propagation in Infinite String Superpositionability of Solutions General Solution of PDE’s 5ÎL § a . § 5 Î L Åħ ∂ 2u ∂t2 −a 2∇2u = f L ≡ ∂ 2 ∂t2 −a 2∇2 9D§ ∂u ∂t −κ∇2u = f L ≡ ∂ ∂t−κ∇2 Poisson§ ∇2u = f L ≡ ∇2 55µ L[α1u1+α2u2] = α1L[u1] + α2L[u2] C. S. Wu 1ù êÆÔn§