# 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 25,903 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 95 121,413 Hello I know nothing about differential equations, can you explain them to me in a few simple words? And what's... Nov1-12 05:48 PM djpailo 33 3,808 Hi, I am in a numerical methods for PDE's class and have just been introduced to the ADI method. My teacher has... Oct30-12 07:15 PM tlonster 0 899 Hi! I am tackling a pretty simple system of rate equations: N1' = -N1/t1 (1) N2' = -N2/t2 + N1/t1 ... Oct30-12 07:18 AM JevKus 0 765 Since the hurricane has killed school for awhile, I was working on some stuff that I knew we would not cover in class... Oct29-12 05:49 PM dochalladay32 0 912 f is a one to one function with inverse f^-1, and we are asked to find the inverse of s(x)=/ My attempts leave me... Oct29-12 11:45 AM tiny-tim 9 1,446 I just don't get why the method of undetermined coefficients can't be applied to tan(x) and sec(x). What my book says... Oct28-12 02:28 AM lurflurf 5 1,473 The Cauchy homogeneous linear differential equation is given by x^{n}\frac{d^{n}y}{dx^{n}} +k_{1}... Oct26-12 02:45 PM HallsofIvy 7 2,738 Hello, First post. I will attempt to use latex, something that involves me jabbing my keyboard with a pen since my... Oct25-12 09:36 PM TehAdzMan 4 1,244 Let's say we have an object falling through an accelerated field from r to s. I would say a gravitational field, as it... Oct25-12 05:17 PM grav-universe 0 700 Hi guys! I had the following system of DE's to solve: \alpha '=-2i \alpha \beta ' =2i \beta. Where alpha and beta... Oct25-12 12:33 AM chiro 2 1,113 Mod note: HTML size = ... tags are not needed. You can make things look just fine using tags instead of tags. So,... Oct24-12 11:20 PM LCKurtz 20 1,557 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 2,501 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 1,168 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 1,481 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 1,160 Here's the proof that I read for method of variation of parameters- ... Oct24-12 09:04 AM iVenky 4 2,672 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 4 956 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 1,752 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 1,148 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 1,127 Hi there, This is a problem concerning hyperbolic type partial differential equations. Currently I am studying the... Oct23-12 01:40 AM OneMoreName 3 1,449 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 0 794 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 1 778 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 1,104 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 5 759 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 2 926 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 1 769 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 1 875 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 1,041 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 1,345 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 1,391 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 1,018 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 1,101 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 1,410 I want to numerically solve some diffusion-type PDEs of the form \frac{\partial u}{\partial t} =... Oct14-12 11:43 AM Mute 0 2,179 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 1,055 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 1,028 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 1,071 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 1,601 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 1 656