Interested Article - Формулы векторного анализа 0 0 ainsleigh 2021-09-11 2 Обозначения оператор набла : ∇ {\displaystyle \nabla } градиент скалярного поля : ∇ ψ = grad ψ {\displaystyle \nabla \psi =\operatorname {grad} \ \psi } дивергенция векторного поля : ∇ ⋅ A = div A {\displaystyle \nabla \cdot \mathbf {A} =\operatorname {div} \ \mathbf {A} } ротор векторного поля : ∇ × A = rot A {\displaystyle \nabla \times \mathbf {A} =\operatorname {rot} \ \mathbf {A} } лапласиан : Δ = ∇ 2 = ∇ ⋅ ∇ {\displaystyle \Delta =\nabla ^{2}=\nabla \cdot \nabla } Линейность Для любого числа α {\displaystyle \alpha } : ∇ ( α ϕ + ψ ) = α ∇ ϕ + ∇ ψ {\displaystyle \ \nabla (\alpha \phi +\psi)=\alpha \nabla \phi +\nabla \psi } g r a d ( α ϕ + ψ ) = α g r a d ϕ + g r a d ψ {\displaystyle \ \mathbf {grad} (\alpha \phi +\psi)=\alpha \ \mathbf {grad} \ \phi +\mathbf {grad} \ \psi } ∇ ⋅ ( α A + B ) = α ∇ ⋅ A + ∇ ⋅ B {\displaystyle \ \nabla \cdot (\alpha \mathbf {A} +\mathbf {B})=\alpha \nabla \cdot \mathbf {A} +\nabla \cdot \mathbf {B} } d i v ( α A + B ) = α d i v A + d i v B {\displaystyle \ \mathbf {div} \ (\alpha \mathbf {A} +\mathbf {B})=\alpha \ \mathbf {div} \ \mathbf {A} +\mathbf {div} \ \mathbf {B} } ∇ × ( α A + B ) = α ∇ × A + ∇ × B {\displaystyle \ \nabla \times (\alpha \mathbf {A} +\mathbf {B})=\alpha \nabla \times \mathbf {A} +\nabla \times \mathbf {B} } r o t ( α A + B ) = α r o t A + r o t B {\displaystyle \ \mathbf {rot} (\alpha \mathbf {A} +\mathbf {B})=\alpha \ \mathbf {rot} \ \mathbf {A} +\mathbf {rot} \ \mathbf {B} } Операторы второго порядка ∇ × ( ∇ ψ ) = 0 {\displaystyle \ \nabla \times (\nabla \psi)=0} r o t ( g r a d ψ ) = 0 {\displaystyle \ \mathbf {rot} (\mathbf {grad} \ \psi)=0} ∇ ⋅ ( ∇ × A ) = 0 {\displaystyle \ \nabla \cdot (\nabla \times \mathbf {A})=0} d i v ( r o t A ) = 0 {\displaystyle \ \mathbf {div} \ (\mathbf {rot} \ \mathbf {A})=0} Δ ψ = ∇ ⋅ ( ∇ ψ ) = ∇ 2 ψ {\displaystyle \ \Delta \ \psi =\nabla \cdot (\nabla \psi)=\nabla ^{2}\psi } Δ ψ = d i v ( g r a d ψ ) {\displaystyle \ \Delta \ \psi =\mathbf {div} \ (\mathbf {grad} \ \psi)} ∇ × ∇ × A = ∇ ( ∇ ⋅ A ) − ∇ 2 A {\displaystyle \ \nabla \times \nabla \times \mathbf {A} =\nabla (\nabla \cdot \mathbf {A})-\nabla ^{2}\mathbf {A} } r o t ( r o t A ) = g r a d ( d i v A ) − Δ A {\displaystyle \ \mathbf {rot} \ (\mathbf {rot} \ \mathbf {A})=\mathbf {grad} \ (\mathbf {div} \ \mathbf {A})-\Delta \mathbf {A} } Дифференцирование произведений полей ∇ ⋅ ( ψ A ) = A ⋅ ∇ ψ + ψ ∇ ⋅ A {\displaystyle \nabla \cdot (\psi \mathbf {A})=\mathbf {A} \cdot \nabla \psi +\psi \nabla \cdot \mathbf {A} } d i v ( ψ A ) = A ⋅ g r a d ψ + ψ d i v A {\displaystyle \mathbf {div} (\psi \mathbf {A})=\mathbf {A} \cdot \mathbf {grad} \psi +\psi \ \mathbf {div} \mathbf {A} } ∇ × ( ψ A ) = ∇ ψ × A + ψ ∇ × A {\displaystyle \nabla \times (\psi \mathbf {A})=\nabla \psi \times \mathbf {A} +\psi \nabla \times \mathbf {A} } r o t ( ψ A ) = g r a d ψ × A + ψ r o t A {\displaystyle \mathbf {rot} (\psi \mathbf {A})=\mathbf {grad} \psi \times \mathbf {A} +\psi \ \mathbf {rot} \mathbf {A} } ∇ ( A ⋅ B ) = ( A ⋅ ∇ ) B + ( B ⋅ ∇ ) A + {\displaystyle \nabla (\mathbf {A} \cdot \mathbf {B})=(\mathbf {A} \cdot \nabla)\mathbf {B} +(\mathbf {B} \cdot \nabla)\mathbf {A} +} + A × ( ∇ × B ) + B × ( ∇ × A ) {\displaystyle +\mathbf {A} \times (\nabla \times \mathbf {B})+\mathbf {B} \times (\nabla \times \mathbf {A})} g r a d ( A ⋅ B ) = ( A ⋅ ∇ ) B + ( B ⋅ ∇ ) A + {\displaystyle \ \mathbf {grad} (\mathbf {A} \cdot \mathbf {B})=(\mathbf {A} \cdot \nabla)\mathbf {B} +(\mathbf {B} \cdot \nabla)\mathbf {A} +} + A × r o t B + B × r o t A {\displaystyle +\mathbf {A} \times \mathbf {rot} \mathbf {B} +\mathbf {B} \times \mathbf {rot} \mathbf {A} } 1 2 ∇ A 2 = A × ( ∇ × A ) + ( A ⋅ ∇ ) A {\displaystyle {\frac {1}{2}}\nabla A^{2}=\mathbf {A} \times (\nabla \times \mathbf {A})+(\mathbf {A} \cdot \nabla)\mathbf {A} } 1 2 g r a d A 2 = A × ( r o t A ) + ( A ⋅ ∇ ) A {\displaystyle {\frac {1}{2}}\ \mathbf {grad} A^{2}=\mathbf {A} \times (\mathbf {rot} \mathbf {A})+(\mathbf {A} \cdot \nabla)\mathbf {A} } ∇ ⋅ ( A × B ) = B ⋅ ∇ × A − A ⋅ ∇ × B {\displaystyle \nabla \cdot (\mathbf {A} \times \mathbf {B})=\mathbf {B} \cdot \nabla \times \mathbf {A} -\mathbf {A} \cdot \nabla \times \mathbf {B} } d i v ( A × B ) = B ⋅ r o t A − A ⋅ r o t B {\displaystyle \mathbf {div} \ (\mathbf {A} \times \mathbf {B})=\mathbf {B} \cdot \mathbf {rot} \ \mathbf {A} -\mathbf {A} \cdot \mathbf {rot} \ \mathbf {B} } ∇ × ( A × B ) = A ( ∇ ⋅ B ) − B ( ∇ ⋅ A ) + {\displaystyle \ \nabla \times (\mathbf {A} \times \mathbf {B})=\mathbf {A} (\nabla \cdot \mathbf {B})-\mathbf {B} (\nabla \cdot \mathbf {A})+} + ( B ⋅ ∇ ) A − ( A ⋅ ∇ ) B {\displaystyle \;+(\mathbf {B} \cdot \nabla)\mathbf {A} -(\mathbf {A} \cdot \nabla)\mathbf {B} } r o t ( A × B ) = A ( d i v B ) − B ( d i v A ) + {\displaystyle \ \mathbf {rot} (\mathbf {A} \times \mathbf {B})=\mathbf {A} \ (\mathbf {div} \ \mathbf {B})-\mathbf {B} \ (\mathbf {div} \ \mathbf {A})+} + ( B ⋅ ∇ ) A − ( A ⋅ ∇ ) B {\displaystyle \;+(\mathbf {B} \cdot \nabla)\mathbf {A} -(\mathbf {A} \cdot \nabla)\mathbf {B} } См. также Векторный анализ Теорема Стокса Оператор набла в различных системах координат 0 0 ainsleigh 2021-09-11 2 Tags:КатегорияВекторный анализ Бюро экономического анализа (США) 1 year ago 0 0 0 Институт системного анализа Российской академии наук 1 year ago 0 0 0