Differential Equations Forum

Join in expert discussion on differential equation topics like ODE and PDE. Differential equations are an equation involving derivatives of a function or functions.

Threads

Graduate Can someone walk me through solving a PDE numerically?

  • cmkluza
  • · Replies 12 ·
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12

Graduate Whittaker's solution and separable variables

  • matt_crouch
  • · Replies 4 ·
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4

Graduate Why does the Green's function method work for PDEs?

  • alivedude
  • · Replies 2 ·
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2

Proving $\int_{\mathbb{R}^3}\Delta G(x,y)dx=1$ with Gauss's Theorem

  • evinda
  • · Replies 1 ·
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1

Graduate Characteristic equation for recurrence equation

  • Bruno Tolentino
  • · Replies 3 ·
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3

Put the 2D nonlinear system into Polar Coordinates

  • Krish23
  • · Replies 1 ·
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1

Undergrad Differentiating an exponential with a complex exponent

  • Zacarias Nason
  • · Replies 7 ·
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7

Graduate How to graph the duffing frequency response

  • Takuza
  • · Replies 1 ·
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1

Graduate Equations with dependent variable missing

  • Joseph1739
  • · Replies 3 ·
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3

Graduate Solution for f(n) in recurrence equation

  • Bruno Tolentino
  • · Replies 1 ·
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1

Graduate Is There a Rigorous Method to Regularize Green's Functions in Coordinate Space?

  • Einj
  • · Replies 1 ·
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1

Graduate Separation of variables with boundary conditions for X_n

  • theone
  • · Replies 4 ·
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4

Graduate A question on Laplace transform

  • Debdut
  • · Replies 3 ·
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3

Graduate Solve Difference Equation: ΔP = e^P

  • Cyrus
  • · Replies 9 ·
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9

Undergrad Why is differential equation equal to sum of partials?

  • cmkluza
  • · Replies 6 ·
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6

Undergrad Phase portrait for dy/dx = ky - w

  • David Donald
  • · Replies 2 ·
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2

Undergrad Attempting to model traffic flow after front car decelerates

  • cmkluza
  • · Replies 6 ·
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6

Graduate When do mixed and second derivative PDEs determine surfaces in R^3?

  • lavinia
  • · Replies 2 ·
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2

Graduate Why does expanding e^(it) give imaginary terms in ODE solution?

  • sa1988
  • · Replies 9 ·
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9

Graduate What are the limitations of using electrical circuits to solve PDEs?

  • Domenico94
  • · Replies 9 ·
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9

Graduate Can two different implicit solutions define the same curve for an ODE?

  • ArenasField
  • · Replies 1 ·
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1

Undergrad Classifying second-order Partial differential equations

  • hellomrrobot
  • · Replies 3 ·
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3

Graduate Vertical diffusion in EPIC GCM

  • rc_nmt
  • · Replies 10 ·
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10

Graduate When can I rename constants in differential equations?

  • Joseph1739
  • · Replies 2 ·
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2

Initial vertical velocity (vertical motion)

  • averyjedwards2
  • · Replies 1 ·
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1

Undergrad Why does multiplying dy/dt by dt give dy using the chain rule?

  • Joseph1739
  • · Replies 8 ·
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8

Creating a 4D System with a Specific Solution: How Can It Be Done?

  • sawdee
  • · Replies 4 ·
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4

Graduate Wronskian and two solutions being independent

  • bubblewrap
  • · Replies 9 ·
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9

Graduate Why does differentiating f(x,y,z,a,b)=0 give fx+pfz=0?

  • ahmed markhoos
  • · Replies 6 ·
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6

Graduate Proving total variation diminishing for a half step scheme

  • martizzle
  • · Replies 3 ·
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3

Undergrad Differentiatial equation

  • TimeRip496
  • · Replies 6 ·
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6

Solving Second Order ODE: True or False?

  • Guest2
  • · Replies 2 ·
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2
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1

Undergrad How do you actually calculate this....?

  • SansaStark
  • · Replies 8 ·
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8

Graduate Variation of parameters - i have different particular soluti

  • omar yahia
  • · Replies 3 ·
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3

Solving 2e^(-x) = 3e^(0.1x) for x

  • Velo
  • · Replies 4 ·
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4

Graduate Brainstorm Ideas for Project - Get Suggestions on Differential Equations

  • faradayscat
  • · Replies 5 ·
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5

Graduate Special Second Order Ordinary Diff. Equation

  • Andreol263
  • · Replies 3 ·
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3

Undergrad Why differential equations? When to use them?

  • Pulik
  • · Replies 11 ·
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11

What is the mistake in this supposed proof?

  • evinda
  • · Replies 5 ·
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5

Undergrad Equation for underdamped harmonic motion

  • pinkcashmere
  • · Replies 2 ·
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2

How do we get the imaginary part?

  • evinda
  • · Replies 4 ·
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4

Undergrad A solved 2nd order ODE that i don't understand its solution

  • omar yahia
  • · Replies 7 ·
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7

Graduate Does Integration Scheme Choice Matter for Initial Demo of Crane Control?

  • observer1
  • · Replies 6 ·
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6

Graduate Green's function in elliptic box

  • Einj
  • · Replies 4 ·
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4

Graduate Solving the 3D Diffusion Equation with Fourier Spectral Techniques

  • johnnyTransform
  • · Replies 2 ·
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2

Undergrad Why 2nd order differential equation has two solutions

  • goodphy
  • · Replies 4 ·
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4

Graduate Why multiply trig polynomials by x in undetermined coefficients

  • kostoglotov
  • · Replies 1 ·
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1

Graduate Transfer function with non zero initial conditions

  • Wesker
  • · Replies 1 ·
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1

Graduate Fitting data to complicated model

  • yumyumyum
  • · Replies 5 ·
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5

Graduate Numerical solution of non-linear diffusion equation

  • maka89
  • · Replies 11 ·
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11

How do I apply the Frobenius method to solve Hermite's ODE?

  • ognik
  • · Replies 1 ·
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1

Graduate Axial/Longitudinal Vibrations in beams

  • Runei
  • · Replies 20 ·
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20

Graduate Are solutions from different values of s in the Frobenius method independent or combined?

  • TroyElliott
  • · Replies 2 ·
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2

How do we deduce that there is such a point?

  • evinda
  • · Replies 2 ·
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2

Undergrad What are differential equations good for?

  • INTP_ty
  • · Replies 2 ·
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2
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1

Find Ansatz for this ODE (3.5.15)

  • ognik
  • · Replies 2 ·
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2

Particular solution for y'' + 3y' - 4y = sin ωt

  • ognik
  • · Replies 3 ·
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3

Graduate Bungee jump -> differential equation -> simulink simulation

  • Wesker
  • · Replies 2 ·
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2

ODE y'' + 4y' - 12y = 0 with initial conditions y(0)=1, y(1)=2

  • ognik
  • · Replies 2 ·
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2

Second-order ODE with initial conditions y'' + 2y' + 3y = 0

  • ognik
  • · Replies 7 ·
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7

Finding the weight function for Laguerre's equation

  • ognik
  • · Replies 5 ·
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5

Graduate Do these two partial derivatives equal each other?

  • thegirl
  • · Replies 4 ·
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4

Graduate Taylor expansion with multi variables

  • bubblewrap
  • · Replies 5 ·
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5

Solving a Difficult DE with TI-NSPIRE: Is it True?

  • karush
  • · Replies 2 ·
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2

Undergrad Why does the Wronskian vanish at x = 0 for linearly independent solutions?

  • kostoglotov
  • · Replies 1 ·
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1

Graduate Soln space basis for all constant coeff homo linear DE's?

  • kostoglotov
  • · Replies 1 ·
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1

Solve for $a^2$ in $u_{xx} = u_{tt}$ using $u_1$ and $u_2$

  • karush
  • · Replies 5 ·
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5

Undergrad How do differential equations relate to traffic flow?

  • cmkluza
  • · Replies 5 ·
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5

Graduate Question on proper technique for solving this equation

  • redtree
  • · Replies 2 ·
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2

Undergrad Solving dy/dx = e^-2y by separable integration

  • santeria13
  • · Replies 4 ·
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4

Differential equation y/(x^2+y^2)

  • Nikolas7
  • · Replies 4 ·
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4

Solve the differential equation

  • Nikolas7
  • · Replies 6 ·
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6

Verifying Solution: U(x, y) = cos(x) cosh(y) for PDE U_xx + U_yy = 0

  • karush
  • · Replies 5 ·
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5

Graduate Why exponential solutions for second order linear differential equations

  • anachin6000
  • · Replies 5 ·
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5

-b.1.3.21-24 Order and linear or nonlinear

  • karush
  • · Replies 6 ·
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6

Undergrad Understanding some unfamiliar words

  • mr.tea
  • · Replies 6 ·
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6

Graduate Why Must B Approach Zero in Cauchy-Euler ODE Solutions at x=0?

  • Andreol263
  • · Replies 4 ·
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4

Graduate A Holder space is a Banach space

  • Domenico94
  • · Replies 12 ·
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12

Converting complex exponential solutions to real trig form

  • ognik
  • · Replies 4 ·
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4

What are the different types and stabilities of critical points?

  • ineedhelpnow
  • · Replies 3 ·
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3

Higher power constant coefficiants ODEs

  • ognik
  • · Replies 2 ·
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2

Solving y'=Ay for a 2×2 matrix system

  • ineedhelpnow
  • · Replies 7 ·
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7

Finding particular solutions with undetermined coefficients

  • ineedhelpnow
  • · Replies 9 ·
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9

How to Find a General Solution Using Variation of Parameters?

  • ineedhelpnow
  • · Replies 2 ·
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2

Undergrad Can All Differential Equations Be Separated?

  • whatisreality
  • · Replies 10 ·
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10

Approximating Equations for Unknowns: How to Justify the Form of $U_0$?

  • evinda
  • · Replies 5 ·
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5

Solutions to Linear Diff. Eq. of 1st Order in a Ring?

  • mathmari
  • · Replies 3 ·
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3

Insights Solving Nonhomogeneous Linear ODEs using Annihilators - Comments

  • Mark44
  • · Replies 5 ·
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5

Undergrad Linear First-Order Differential Equation

  • DiamondV
  • · Replies 3 ·
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3

Graduate Solving a PDE w/ given boundary and initial conditions

  • TheCanadian
  • · Replies 5 ·
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5

Graduate Failure to see the validity of an approximation to DiffEq.

  • davidbenari
  • · Replies 3 ·
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3

Graduate How Does Laplace Transform Solve the Harmonic Motion Differential Equation?

  • Jim wah
  • · Replies 2 ·
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2

Reducing a system of differential equations to a single equation

  • mathmari
  • · Replies 5 ·
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5

Are Unique Solutions Possible for Homogeneous Equations?

  • mathmari
  • · Replies 1 ·
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1

Graduate Finite-element solution of Sturm-Liouville problem

  • leon_avery
  • · Replies 2 ·
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2

Solving a PDE using separation of variables

  • arrow27
  • · Replies 1 ·
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1

Undergrad Finding s1 from dominant closed loop poles

  • shayaan_musta
  • · Replies 4 ·
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4

Graduate Find the approximate linear ODE system

  • NiallBucks
  • · Replies 6 ·
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6