Differential Equations Forum

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Join in expert discussion on differential equation topics like ODE and PDE. Differential equations are an equation involving derivatives of a function or functions.
  • Sticky
Undergrad Intro. to Differential Equations
  • ExtravagantDreams
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Undergrad Mixed approximation vs. full approximation for a power series expansion
  • FranzS
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Undergrad Correct Upper/Lower limits for continuation of solutions for ODE
  • elias001
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Undergrad 2nd order ODE's, variation of parameters and the notorious constraint
  • haushofer
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Undergrad A question about variables of integration
  • Rick16
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Graduate About ellipticity and a proof that a system of PDEs is elliptic
  • fluidistic
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Graduate Volterra equation of the second kind
  • reterty
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High School An exact Paraxial equation derivation, 100% Cartesian
  • difalcojr
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Undergrad Direction Fields and Isoclines
  • Kakashi
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Graduate Should the boundary condition have to satisfy dimensional consistency?
  • SaleemKU
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Undergrad Why Lagrange’s method of solving Pp + Qq=R works?
  • PLAGUE
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Graduate Show positivity and boundedness of a non-linear system
  • dgf
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Graduate The heat equation for a composite having contact resistance
  • shreddinglicks
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Undergrad Visual Representation of Separation of Varables
  • sonnichs
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Undergrad Solving a system of equations with 5 unknowns
  • hmparticle9
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Undergrad Understanding Legendre differential equation
  • chwala
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Undergrad Proving a basis is a basis for homogeneous linear differential equation with constant (complex) coefficients
  • psie
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Graduate Searching for radial part solution of Klein-Gordon type equation
  • art1915
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Undergrad 1D time dependent PDE - using orthogonal collocation
  • mayzal
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Graduate Boundary conditions sufficient to ensure uniqueness of solution?
  • fluidistic
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High School Mathematical equation of motion of a differential two-wheeled Sumo robot
  • dis
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High School Deriving an asymmetric logistic growth model
  • liquidFuzz
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Graduate Solving for a steady-state (passive cable equation)
  • rall1959
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Undergrad Stuck on solving a non homogenous (linear) PDE
  • fluidistic
  • · Replies 36 ·
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Undergrad Solving ODE with Laplace transform and Existence and Uniqueness Theorem
  • lys04
  • · Replies 19 ·
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Graduate Symplectic split of Hamiltonian with complex term
  • ematt
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Graduate Computing end-points using the Neumann condition
  • hunt_mat
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Graduate Need help with Rodrigues formula example in Riley, Hobson, Bence - Mathematical Methods for Physics and Engineering 3rd edition
  • vgarg
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Undergrad When is an ODE (numerically) reversible in time?
  • Aidyan
  • · Replies 4 ·
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Undergrad Question about the general solution to Hooke's law
  • dainceptionman_02
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Undergrad How to do Magnus expansion for time-dependent companion matrix?
  • adf89812
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Graduate How to use the Newton-Raphson method while keeping the sum constant?
  • K-Manu
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Graduate Request resources to understand Picard–Lindelöf for ODEs
  • adf89812
  • · Replies 6 ·
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Undergrad Relevant Literature for Noisy Linear Dynamical Systems
  • scjiang
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Undergrad Energy of moving Sine-Gordon breather
  • TOAsh2004
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Undergrad Runge-Kutta 4 w/ some sugar on the top: How to do error approximation?
  • bremenfallturm
  • · Replies 65 ·
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Undergrad Maxwell's equations PDE interdependence and solutions
  • cianfa72
  • · Replies 5 ·
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Undergrad Understanding the given transformation - PDE
  • chwala
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Undergrad A step in a proof of linear dependence of ODE solutions
  • Hill
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High School Solving Kepler's 1st law as a function of time
  • jebez
  • · Replies 23 ·
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Graduate Heat conduction equation in cylindrical coordinates
  • shreddinglicks
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Undergrad Numerically how to approximate exponential decay in a discrete signal
  • cppIStough
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Graduate Circuit ODE with multiple short voltage impulses
  • ishan_ae
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Undergrad Number of solutions to the order of the equation
  • Trying2Learn
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Undergrad Numerically solving a non-local PDE
  • ergospherical
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Undergrad Green's function for 2-D Laplacian within square/rectangular boundary
  • Swamp Thing
  • · Replies 5 ·
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Undergrad Toy problem to motivate the idea of advanced Green's functions
  • Swamp Thing
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Undergrad How to Solve a Nonlinear PDE with Sinh Function?
  • Adri
  • · Replies 4 ·
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Graduate Navier-Stokes solutions: Beltrami flow
  • casparov
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Undergrad Partial Differential Equation solved using Products
  • mathhabibi
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Undergrad Detailed solution of an envelopes example in a math book
  • vgarg
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Undergrad General solution vs particular solution
  • sdfsfasdfasf
  • · Replies 52 ·
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Graduate A question about an 'extremal' surface
  • Antarres
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Graduate Why is the Heat equation solved with separation of variables but not with Fourier transformations?
  • yaman
  • · Replies 4 ·
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Undergrad Uniform convergence of functions
  • chwala
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Undergrad On vibrating string and differentiating infinite sum
  • psie
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Undergrad Determining the dimension of a given PDE
  • chwala
  • · Replies 9 ·
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Undergrad Navier-Stokes equation in a triangular coordinate system
  • MasterOgon
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Undergrad Getting zeros and poles for Laplace transform
  • bnich
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Undergrad V * grad(V) = grad(V^2/2) - rotor(omega)
  • Rikyuri
  • · Replies 6 ·
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Graduate SDE valuation equation (stochastic calculus)
  • cppIStough
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Insights Differential Equation Systems and Nature
  • fresh_42
  • · Replies 14 ·
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Undergrad LIF Neuron Equation Solution for arbitrary time-dependent current (Neural Dynamics)
  • gigorina
  • · Replies 0 ·
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Undergrad Determining linear indepedence/dependence of a set of functions
  • chwala
  • · Replies 11 ·
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Undergrad Reduction of order in solving second order differential equations
  • chwala
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Undergrad Heavyside’s operational calculus vs. transforms
  • Frabjous
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Undergrad How to Evaluate This Stochastic Expectation Value?
  • thatboi
  • · Replies 0 ·
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Undergrad Differential equation using power series method
  • Graham87
  • · Replies 8 ·
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Undergrad Find the directional derivative of ##f## at the given point
  • chwala
  • · Replies 3 ·
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Undergrad Determining equilibrium solutions to differential equations
  • chwala
  • · Replies 16 ·
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Undergrad Cylindrical coordinates -Curvilinear
  • chwala
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Undergrad The constant value on the given exact differential equation
  • chwala
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Undergrad Determining directional Field for say ##\dfrac{dy}{dx}=y-x##
  • chwala
  • · Replies 5 ·
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Graduate Solve PDE w/ Comsol 5.3: Numerical Solution & Time Evolution
  • umby
  • · Replies 5 ·
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Graduate Discretisation of a PDE in Lagrangian coordinates
  • hunt_mat
  • · Replies 4 ·
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Undergrad Good positing in electrostatics problem with dielectrics - Poisson problem with conditions at the Dirichlet or Neumann edge
  • Hak
  • · Replies 1 ·
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High School Solving PDEs via FEM: A Gut Check of the Procedure
  • Vanilla Gorilla
  • · Replies 0 ·
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Undergrad On a bijective Laplace transform
  • psie
  • · Replies 1 ·
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Undergrad Modeling Asteroid Rotation Using Quaternions: Seeking Guidance on Init
  • Codezero
  • · Replies 3 ·
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Undergrad On Laplace transform of derivative
  • psie
  • · Replies 17 ·
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Graduate Legendre Polynomials -- Jackson Derivation
  • Reverend Shabazz
  • · Replies 6 ·
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High School Incorporating boundary conditions in the Finite Element Method (FEM)
  • Vanilla Gorilla
  • · Replies 4 ·
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Undergrad On sub and super solutions: Teschl and others
  • psie
  • · Replies 5 ·
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Graduate Integrability of Systems of Differential Equations
  • The Tortoise-Man
  • · Replies 5 ·
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Undergrad On the approximate solution obtained through Euler's method
  • psie
  • · Replies 1 ·
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Undergrad On error estimates of approximate solutions
  • psie
  • · Replies 1 ·
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Undergrad Feynmann's connection machine model
  • picketpocket826
  • · Replies 1 ·
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Undergrad Verifying properties of Green's function
  • psie
  • · Replies 1 ·
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Undergrad Question about solving linear first order non-homogeneous ODEs
  • CGandC
  • · Replies 3 ·
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Undergrad Solving Differential Equation Using Reduction of Order
  • giodude
  • · Replies 2 ·
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Graduate Stability analysis for numerical schemes of systems of PDEs
  • hunt_mat
  • · Replies 1 ·
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Graduate The field equations of elasticity
  • Trying2Learn
  • · Replies 6 ·
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Undergrad Heat Equation: Solve with Non-Homogeneous Boundary Conditions
  • erobz
  • · Replies 4 ·
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Graduate Solving System of PDEs: Analytical Methods & Solutions
  • satu
  • · Replies 9 ·
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Undergrad Solve Int. Eq.: Exponential Growth Diff. Eq.
  • mcastillo356
  • · Replies 7 ·
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Undergrad "Rationale" for Homogeneous vs. Nonhomogeneous Differential Equations?
  • Martyn Arthur
  • · Replies 10 ·
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Graduate Obtaining a variable value from a 5-th degree polynomial in the tangent form
  • baby_1
  • · Replies 4 ·
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Graduate How to work around this equation giving infinities in the numerical calculation?
  • FQVBSina_Jesse
  • · Replies 4 ·
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Undergrad Finding the time for the first shock for a quasilinear first order PDE
  • BloonAinte
  • · Replies 4 ·
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Graduate Separation of variables is possible only in 11 coordinate systems?
  • Trying2Learn
  • · Replies 7 ·
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Graduate Numerically solving a transport equation
  • hunt_mat
  • · Replies 3 ·
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