
Please post any and all homework or other textbookstyle problems in one of the Homework & Coursework Questions...

Feb2313 09:24 AM
micromass

1 
30,383 
My intent is to create a thread for people interested in Differential Equations. However, I will explicitly state that...

Jul312 07:18 PM
Luccas

95 
138,990 
Hey I am in physics 30 and i am having trouble rearraging this eqaution: d=vt+1/2at^2
V= velocity 1
a=...

Oct2412 04:58 PM
kimberlycc

2 
1,255 
Here's the proof that I read for method of variation of parameters
...

Oct2412 09:04 AM
iVenky

4 
2,853 
I have a doubt in finding out the Particular Integral of eaxV, where 'V' is a function of x.
I saw the book but...

Oct2312 10:51 PM
iVenky

4 
1,067 
Consider a circle of radius 'a' and centre (h,b)
then the equation of the circle is given by (xh)2 + (yb)2 = a2
...

Oct2312 05:12 PM
Chestermiller

4 
1,960 
Hello there,
I want to solve the heat PDE in a 1D domain for a source moving at constant speed. The problem has...

Oct2312 10:57 AM
muzialis

4 
1,250 
I was recently trying to prove the variation of parameters formula for an nth degree equation, and I have come up with...

Oct2312 08:07 AM
HallsofIvy

1 
1,284 
Hi there,
This is a problem concerning hyperbolic type partial differential equations. Currently I am studying the...

Oct2312 01:40 AM
OneMoreName

3 
1,722 
I was wondering if someone can show me or point me to a worked out example using integration by parts for more than...

Oct2212 10:19 PM
ericm1234

0 
899 
Actually I can't find if a differential equation is homogeneous or not
I thought homogeneous is given by
dy/dx=...

Oct2212 01:35 PM
Vargo

1 
881 
Hi! I am currently working with a linear PDE on the form
\frac{\partial f}{\partial t} + A(v^2 ...

Oct2112 06:32 PM
sith

5 
1,249 
Hi everybody,
For part of my research, I need to solve an elliptic PDE like:
Δu  k * u = 0,
subject to : 0≤...

Oct2012 10:32 PM
haruspex

5 
822 
All,
I have a system of three coupled PDE and I discretized the equations using finite difference method.
It...

Oct2012 05:29 PM
FrankST

2 
1,036 
Hi,
I am undertaking an undergrad design project and want to ensure I'm doing this correctly,
I have derived the...

Oct2012 01:40 PM
X89codered89X

1 
846 
Does it have an easy classification (elliptic, hyperbolic, parabolic, for example)? Or does the fact that it has an...

Oct1912 04:24 PM
Mute

1 
1,158 
Hi,
I was wondering if you can apply shooting method to a 4nd differential eq.
two point value boundary problem,
...

Oct1712 10:23 PM
Chestermiller

2 
1,162 
Hello, I have recently started a little implicit differentiation and I have seen DEs before but I know that I still...

Oct1712 08:49 AM
Mute

1 
1,586 
dε/dt=d(uε)/dZ+
where ε=% area opening, u= velocity, Z=length , k1, k2= constants, t= time
Please help me how...

Oct1612 07:12 AM
Chestermiller

5 
1,493 
Suppose I have a really simple first order linear ODE like:$$\dot{\omega} = k\omega$$ where k is some constant, ω(t)...

Oct1512 07:38 PM
cepheid

2 
1,090 
Hi. I'm watching this video and I don't know what the lecturer is saying.
In this video, he says something like...

Oct1412 10:27 PM
OmCheeto

1 
1,184 
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...

Oct1412 07:22 PM
X89codered89X

5 
1,526 
I want to numerically solve some diffusiontype PDEs of the form
$$\frac{\partial u}{\partial t} =...

Oct1412 11:43 AM
Mute

0 
2,566 
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)...

Oct1412 09:36 AM
galuoises

3 
1,168 
Hi!
I have some trouble understanding this question. Could someone help me with it? Thanks!
Solve the following...

Oct1412 06:37 AM
HallsofIvy

1 
1,105 
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...

Oct1212 06:15 PM
AlephZero

3 
1,208 
Hi, I am using the central difference method to solve a diffusionbased partial differential equation. However, my...

Oct1112 01:42 PM
bigfooted

7 
1,979 
Hi,
I want to solve the EulerBernoulli eq numerically using a c++ library.
EI y^{4}(x)=f(x),...

Oct1112 10:57 AM
Mute

1 
707 
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...

Oct1012 08:40 AM
HallsofIvy

5 
1,245 
find a solution of (a^2x^2)y''2xy'+n(n+1)y=0, a not 0 by reduction to the legendre equation???

Oct1012 08:32 AM
HallsofIvy

3 
1,338 
Dear Friends,
Would you please provide me with some hints to find the analytical solution of the nonlinear PDE given...

Oct912 05:37 AM
mohammad449

2 
918 
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...

Oct812 06:21 AM
micromass

16 
7,816 
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...

Oct712 03:36 AM
Shan K

9 
1,823 
Dear Friends,
I encountered with some difficulties in solving following PDE (off course, analytically not...

Oct612 02:42 AM
mohammad449

4 
1,579 
Hi guys, is there a general method by which to solve a differential equation of form:
D(t)=h'(t)(1/h'(t))' +...

Oct512 06:49 AM
Aspiring

0 
942 
Dear All,
I am working on electrical modeling which I cannot change divergence to matrix form to solve it with...

Oct412 08:47 PM
AGerami

0 
983 
Hello there,
I have read in a paper the following statement,
"due to the nonconservtaivness of the system the...

Oct412 02:01 PM
muzialis

0 
843 
If Po dollars are deposited in an account paying r percent compounded continuously and withdrawals are at a rate of...

Oct412 11:20 AM
Chestermiller

3 
1,147 
Hello all~
Given the equation:
dy/dx = (x/y)
I know we would initially go to:
∫dy =∫ (x/y) dx
then too:...

Oct312 11:54 AM
Studiot

3 
1,212 
I've had to take diff eqtns now and I'm trying to get my head around Laplace again.. it's been a while. I can't seem...

Oct212 05:55 AM
chief10

24 
2,247 
HOW IS THE FOLLOWING QUESTION DONE?
Milk chocolate is being produced in a 300 litre tank, which initially...

Oct112 09:56 PM
nishcha7

3 
1,670 
now say we have cos^2(3t), how would you go about computing it with the 3t?
i can manage cos^2(t) but i'm not sure...

Oct112 10:39 AM
chief10

2 
1,616 