# Differential Equations

- An equation involving derivatives of a function or functions. Solving ODE and PDE
 Meta Thread / Thread Starter Last Post Replies Views Please post any and all homework or other textbook-style problems in one of the Homework & Coursework Questions... Feb23-13 09:24 AM micromass 1 25,819 Pinned: Intro. to Differential Equations ( 1 2 3 ... Last) My intent is to create a thread for people interested in Differential Equations. However, I will explicitly state that... Jul3-12 07:18 PM Luccas 95 121,150 Hello every one. I'm doing research related to heat transfer stuff. I came up with this PDE after making some... Oct24-12 10:36 PM p.sarafraz 4 2,500 I can prove that the particular integral of sin(ax+b) is given by \frac{1}{f(-a^{2})} sin(ax+b) That's not an... Oct24-12 10:10 PM iVenky 2 1,161 After a short look on the question formulated in this differential equation forum I came to the conclusion that the... Oct24-12 08:03 PM Unstable 8 1,474 Hey I am in physics 30 and i am having trouble rearraging this eqaution: d=vt+1/2at^2 V= velocity 1 a=... Oct24-12 04:58 PM kimberlycc 2 1,155 Here's the proof that I read for method of variation of parameters- ... Oct24-12 09:04 AM iVenky 4 2,654 I have a doubt in finding out the Particular Integral of eaxV, where 'V' is a function of x. I saw the book but... Oct23-12 10:51 PM iVenky 4 947 Consider a circle of radius 'a' and centre (h,b) then the equation of the circle is given by (x-h)2 + (y-b)2 = a2 ... Oct23-12 05:12 PM Chestermiller 4 1,742 Hello there, I want to solve the heat PDE in a 1D domain for a source moving at constant speed. The problem has... Oct23-12 10:57 AM muzialis 4 1,139 I was recently trying to prove the variation of parameters formula for an nth degree equation, and I have come up with... Oct23-12 08:07 AM HallsofIvy 1 1,117 Hi there, This is a problem concerning hyperbolic type partial differential equations. Currently I am studying the... Oct23-12 01:40 AM OneMoreName 3 1,429 I was wondering if someone can show me or point me to a worked out example using integration by parts for more than... Oct22-12 10:19 PM ericm1234 0 788 Actually I can't find if a differential equation is homogeneous or not I thought homogeneous is given by dy/dx=... Oct22-12 01:35 PM Vargo 1 773 Hi! I am currently working with a linear PDE on the form \frac{\partial f}{\partial t} + A(v^2 -... Oct21-12 06:32 PM sith 5 1,094 Hi everybody, For part of my research, I need to solve an elliptic PDE like: Δu - k * u = 0, subject to : 0≤... Oct20-12 10:32 PM haruspex 5 755 All, I have a system of three coupled PDE and I discretized the equations using finite difference method. It... Oct20-12 05:29 PM FrankST 2 919 Hi, I am undertaking an undergrad design project and want to ensure I'm doing this correctly, I have derived the... Oct20-12 01:40 PM X89codered89X 1 765 Does it have an easy classification (elliptic, hyperbolic, parabolic, for example)? Or does the fact that it has an... Oct19-12 04:24 PM Mute 1 872 Hi, I was wondering if you can apply shooting method to a 4nd differential eq. two point value boundary problem, ... Oct17-12 10:23 PM Chestermiller 2 1,035 Hello, I have recently started a little implicit differentiation and I have seen DEs before but I know that I still... Oct17-12 08:49 AM Mute 1 1,330 dε/dt=d(uε)/dZ+ where ε=% area opening, u= velocity, Z=length , k1, k2= constants, t= time Please help me how... Oct16-12 07:12 AM Chestermiller 5 1,387 Suppose I have a really simple first order linear ODE like:$$\dot{\omega} = -k\omega$$ where k is some constant, ω(t)... Oct15-12 07:38 PM cepheid 2 1,011 Hi. I'm watching this video and I don't know what the lecturer is saying. In this video, he says something like... Oct14-12 10:27 PM OmCheeto 1 1,095 THE PROBLEM : y(t) = e^(-t)*sin(t^2); with t0 = 0 and T = 3.14159. Find y_0, and use it to deduce the... Oct14-12 07:22 PM X89codered89X 5 1,405 I want to numerically solve some diffusion-type PDEs of the form \frac{\partial u}{\partial t} =... Oct14-12 11:43 AM Mute 0 2,149 Someone know how to uncouple this system of pde? Δu_{1}(x) + a u_{1}(x) + b u_{2}(x) =f(x) Δu_{2}(x) + c u_{1}(x)... Oct14-12 09:36 AM galuoises 3 1,050 Hi! I have some trouble understanding this question. Could someone help me with it? Thanks! Solve the following... Oct14-12 06:37 AM HallsofIvy 1 1,024 Hi, How can one use back Euler method for 2nd order d.e? Is it possible this method to be expanded for a system of... Oct12-12 06:15 PM AlephZero 3 1,065 Hi, I am using the central difference method to solve a diffusion-based partial differential equation. However, my... Oct11-12 01:42 PM bigfooted 7 1,594 Hi, I want to solve the Euler-Bernoulli eq numerically using a c++ library. EI y^{4}(x)=f(x),... Oct11-12 10:57 AM Mute 1 652 A first order DE models the rate of change, e.g. when decay is proportional to time we have the DE: dM/dt = -K.M; this... Oct10-12 08:40 AM HallsofIvy 5 1,137 find a solution of (a^2-x^2)y''-2xy'+n(n+1)y=0, a not 0 by reduction to the legendre equation??? Oct10-12 08:32 AM HallsofIvy 3 1,224 Dear Friends, Would you please provide me with some hints to find the analytical solution of the non-linear PDE given... Oct9-12 05:37 AM mohammad449 2 852 I thought I've seen one, but I do not understand exactly how they negate. For example, if you have d/dx^2 + 1, does... Oct8-12 06:21 AM micromass 16 7,074 I wish to transform my diff. eq. (1/r)*(dy/dr)*(d2/dr2(r*y))*dr into a more convenient expression, in a similar to... Oct7-12 03:36 AM Shan K 9 1,641 Dear Friends, I encountered with some difficulties in solving following PDE (off course, analytically not... Oct6-12 02:42 AM mohammad449 4 1,505 Hi guys, is there a general method by which to solve a differential equation of form: D(t)=h'(t)(1/h'(t))' +... Oct5-12 06:49 AM Aspiring 0 883 Dear All, I am working on electrical modeling which I cannot change divergence to matrix form to solve it with... Oct4-12 08:47 PM AGerami 0 903 Hello there, I have read in a paper the following statement, "due to the non-conservtaivness of the system the... Oct4-12 02:01 PM muzialis 0 748 If Po dollars are deposited in an account paying r percent compounded continuously and withdrawals are at a rate of... Oct4-12 11:20 AM Chestermiller 3 1,036 Hello all~ Given the equation: dy/dx = (x/y) I know we would initially go to: ∫dy =∫ (x/y) dx then too:... Oct3-12 11:54 AM Studiot 3 1,092