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

Feb2313 09:24 AM
micromass

1 
25,835 
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 
121,204 
Hello,
How does the change of variables ## \alpha = x + at , \quad \beta = x  at ## change the differential...

Dec3013 07:03 PM
piercebeatz

1 
451 
I am working on a motorcycle dynamics problem. I have written the equations of motion in matrix form in matlab (and...

Dec2613 08:21 PM
gopi9

8 
1,099 
In our differential equations class, we learned about Ordinary and Regular Singular Points of a differential equation....

Dec2413 01:56 PM
AlephZero

2 
558 
I've come across this problem while self studying Ordinary Differential Equations and I really need help. The problem...

Dec2313 10:51 AM
vanceEE

11 
770 
How to solve this differential equation
\left(\frac{dy}{dx}\right)^{4}+B\left(\frac{dy}{dx}\right)^{3}+C=0
...

Dec2213 08:30 PM
berkeman

2 
803 
Is there a derivation for ∂f(x,y)/∂x given:
f(x,y): g(x,y)h(x,y)
e.g. sin(x)(x+2y)

Dec2113 09:18 AM
BobV

2 
556 
Is there an explicit equation for the StormerVerlet numerical integration method for any problem?
I usually only see...

Dec2113 04:05 AM
bigfooted

3 
1,766 
Suppose I have a variable separable ODE, e.g.,
\frac{dy}{dx} = 3y.
We all know that the solution is y=Ae^{3x}...

Dec2013 09:11 AM
HallsofIvy

1 
466 
By using frobenius method I find the roots of the indicial equation of a 4th order ODE to be
0, 1, 1, 2
Now, what is...

Dec1913 10:44 AM
eradi

2 
555 
http://calclab.math.tamu.edu/~fulling/m412/f07/airywkb.pdf
Can someone walk me through this derivation of the Airy...

Dec1613 07:13 PM
ChrisVer

1 
519 
1. For a nonhomogeneous, linear, 2nd order DE, using the method of undermined coefficients, what do you use for the...

Dec1513 10:35 PM
Jd0g33

4 
428 
This isn't a home work, so only I'm posting here
When we solve y'=cos(πx) we'll get y=sin(πx)/π +C. But...

Dec1513 09:05 AM
ajayguhan

1 
482 
Many times while applying Method of Frobenius, we can also obtain r by equating to zero, the terms involving (r+1)th,...

Dec1513 04:45 AM
gikiian

0 
433 
I was reading and searching about a theory that originated the laplace transfom...

Dec1413 04:58 PM
Jhenrique

0 
573 
Friends I have one doubt
Below given equation is linear or non linear
:)

Dec1413 04:42 PM
Jhenrique

5 
593 
Suppose I have this operator:
##D^2+2D+1##.
Is the ##1## there, when applied to a function, considered as...

Dec1313 09:45 PM
Seydlitz

2 
515 
Usually, when considering the biharmonic equation (given by Δ^2u=f, we look for weak solutions in H^2_0(U), which...

Dec1213 08:45 PM
Arkuski

0 
466 
1) If u(r,\theta,\phi)=\frac{1}{r}, is \frac{\partial{u}}{\partial {\theta}}=\frac{\partial{u}}{\partial {\phi}}=0...

Dec1113 08:25 PM
jasonRF

4 
563 
Dear all,
I have problem to find the differential equation for my circuit shown in the attached picture.
For...

Dec1113 02:06 AM
ntmkd

2 
557 
I've been trying to solve the Romeo and Juliet problem in differential equations:
Romeo is in love with Juliet, but...

Dec1013 10:21 PM
ckelly94

9 
1,955 
Find a topological conjugation between g(x) and T(x) where g and T are mappings (both tent maps )
g: →
g(x) =...

Dec1013 02:31 PM
selig5560

0 
459 
For spherical coordinates, u(r,\theta,\phi) is function of r,\theta,\phi. a is constant and is the radius of the...

Dec1013 12:57 AM
fzero

1 
500 
Want to understand a concept here about dimensions of a function.
Using example 1: a simple fourier series from...

Dec913 01:39 PM
HallsofIvy

1 
567 
Here is the DE:
Δu(r,θ)=0, 1 ≤ r ≤ 2, 0 ≤ θ ≤ pi
and here are the Boundary Conditions:
u(1,θ)=sin(θ), u(2,θ)=0,...

Dec913 10:22 AM
pasmith

1 
577 
Hello,I have a problem in writing my code in Mathematica, when I put values of R,T,S&a the system worked and gave me...

Dec713 06:33 PM
Bill Simpson

4 
671 
\frac{\partial{u}}{\partial{t}}=\frac{\partial^2{u}}{\partial{r}^2}+ \frac {2}{r} \frac...

Dec513 08:14 PM
jasonRF

13 
861 
Dear All,
I have following first order nonlinear ordinary differential and i was wondering if you can suggest some...

Dec513 05:44 AM
epenguin

5 
1,141 
Hi everybody,
I'd like to solve the following "free boundary PDE" numerically. Does anybody knows about some...

Dec413 03:35 AM
re444

0 
495 
I have two questions:
(1)As the tittle, if u(a,\theta,t)=0, is
\frac{\partial{u}}{\partial...

Dec313 01:44 PM
yungman

5 
634 
In Bessel's ODE x^{2}y''+xy''+(x^{2}\nu^{2})y=0, why must \nu not be less than zero?
I have looked it up, but I...

Dec313 12:28 AM
yungman

5 
656 
Hello Guys.
I have to solve two coupled PDE coming from a quantum physical problem, which possess a cylindrical...

Dec113 06:45 AM
Physteo

0 
501 
Hello,
Background:
I was going to implement an implicit approach to 3d tetrahedra deformations (first in Matlab...

Nov3013 04:09 PM
datahead8888

0 
555 
Consider the ODE x(x1)y''xy'+y=0.
I need help in identifying the method of solution (power series or frobenius)...

Nov3013 04:01 AM
JJacquelin

1 
576 
Hello, I am working on a research problem and I am not sure whether or not I will be able to figure this out in a...

Nov3013 03:39 AM
JJacquelin

2 
609 
What is the answer of this differential equation.
((d^2) r)/((ds)^2) +(m/(r^2)) (nr/3)=0
the boundary...

Nov2913 02:14 PM
kumudumalee

2 
521 
I have not met differential equations involving the composition functions (also not much literature on it).
Assume...

Nov2813 11:17 AM
dftfunctional

5 
679 
Consider the ODE y''+P(x)y'+Q(x)y=0.
If \stackrel{limit}{_{x→x_{o}}}P(x) and \stackrel{limit}{_{x→x_{o}}}Q(x)...

Nov2713 02:47 AM
gikiian

2 
684 
Hello,
We were introduced to Laplace transforms in my ODE class a few days ago, so naturally I went online to try...

Nov2613 12:08 PM
AlephZero

2 
689 
I was working on PDE for a project and needed to compute a Jacobian for it.
Suppose we have a function consisting...

Nov2413 01:19 PM
datahead8888

0 
717 
We first express Bessel's Equation in SturmLiouville form through a substitution:
...

Nov2413 10:39 AM
pasmith

2 
660 