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

Feb2313 09:24 AM
micromass

1 
29,623 
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 
136,750 
I used the linear equation method to solve a D.E. and got y=3/4 at the end. I'm asked to find the interval of...

Jan2813 12:41 AM
Mark44

5 
739 
I get confused when it is 'ok' to use the natural logarithm when integrating a function. As soon as I see a...

May2510 03:00 AM
Shaybay92

2 
2,741 
On a 2 dimensional Riemannian manifold when is a vector field with isolated singularities the Lie bracket of two...

Sep1311 01:58 PM
lavinia

0 
970 
Greetings, I faced with a problem that states  Find slope of the tangent line to 〖 x〗^4 –
xy^2+ 4xy^2 = 20,at...

Oct2310 11:37 PM
ngm01

2 
1,156 
Apparently it is a wellknown fact that if G(x)=(G_{ij}(x_1,\ldots,x_n)) is a smooth nxn matrixvalued function such...

Mar2014 03:04 PM
quasar987

0 
461 
I'm doing a course in PDEs, where the lecturer hasn't really explain when all these methods for solving PDEs are...

Nov409 11:52 PM
jasonRF

2 
1,144 
I have some confusion about when separation variables can be applied to a PDE. Can it be applied on any PDE that can...

Apr610 10:15 PM
hosun

1 
714 
I have to find a nontrivial, linear combination of the following functions that vanishes identically.
In other...

Nov410 07:45 PM
warfreak131

6 
3,817 
Just a small list, mark up any others I have neglected... :cool:
edit: already see, I should've put in PDEs with...

Mar2706 10:46 PM
Clausius2

2 
1,535 
I have an equation like this,
\frac{dZ}{zD\beta} = \frac{d}{d\beta}\ln Z,
is it from...

May613 10:36 AM
pattisahusiwa

3 
611 
I recently came across the NS millennium problem and I read that uniqueness for the NS equations is unknown. I have...

Nov411 06:13 PM
myshadow

2 
1,729 
I show a graph where errors in perceived angles of stimuli increase with the underestimation of lengths of stimuli. I...

Feb2012 12:26 PM
PatternSeeker

4 
1,322 
I'm learning fluid mechanics, and I am confused about the following differential operators. What's the difference...

Apr2310 03:06 AM
Thaakisfox

1 
894 
As the thread title says: What's the difference between initial conditions and boundary conditions?
Thanks in...

Mar3109 06:43 PM
HallsofIvy

9 
19,777 
That's my question,let's suppose i define the functions:
G(x,s)=exp(xs)^{2} and R(x,s)=(e^{st}1)^{1}
My...

Oct1106 11:05 AM
Karlisbad

0 
1,555 
Hi there,
My equation to solve is (xy+(x^2))dx + (1)dy=0
For method of exact solutions, the partials are not...

Oct2911 08:12 AM
lurflurf

1 
1,418 
I've been working through an equation for awhile and finally reduced it to a differential equation I have to solve,...

Aug2405 11:56 PM
Lyuokdea

9 
1,535 
Hi all!
In this differentail equation, what particular should I try?
Is it correct to try
" exp(2x)"?

May1505 07:40 PM
saltydog

15 
2,094 
Just learned that diffusion equation loses information as time goes on,i.e. given the initial condition at t=0, we...

Feb2411 05:48 AM
kof9595995

0 
583 
I'm trying to follow a proof for the solution of the diffusion equation in 0 < x < l with inhomogeneous boundary...

Oct310 03:30 PM
jackmell

1 
1,089 
I am trying to solve a realworld problem, and I have modeled it with the following equation:
\frac{dS}{dt}3\left...

Nov511 06:15 PM
yus310

4 
1,748 
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 
1,104 
Hi all.
I am reading things about wave theory.
I am rather confused about the term "weakly nonlinear".
Say for the...

Jun2710 07:02 AM
HallsofIvy

3 
3,550 
Hello everybody, What is this equation called? I'm from nonEnglish speaking country and I need to look up materials...

Jun2113 12:29 PM
Goethe10

6 
768 
When I was scanning the materials of Bessel function, I found that when the variable is:
xe^{\frac{3\pi}{4}i}
...

Feb2712 07:29 PM
Chuck88

8 
1,919 
I'm trying to analyze the following Ito stochastic differential equation:
$$dX_t = \X_t\dW_t$$
where X_t,...

Apr1814 06:57 PM
Only a Mirage

2 
318 
Hi Max,
Thanks very much, but now I am puzzled solving this problem:
F'''+FF''/2=0
F'(infinite)=1...

May2904 05:19 PM
Clausius2

4 
1,888 
I am seeking an EXACT solution of this sistem of ODE's, in which g(x) and f(x) are the unknown functions:
...

May1004 03:14 PM
Clausius2

26 
3,900 
how can we solve this differential equation?
(ax+y)∂f/∂x + (ay+x)∂f/∂y =0 with this condition: if a=0...

May914 02:29 AM
JJacquelin

2 
333 
I have flipped through the first few pages of Evan's PDE book lately, and I am considering taking a graduate PDE...

Aug2409 04:57 PM
ephedyn

6 
1,883 
Hi everyone, I'm currently learning about finiteelement methods and I'm having trouble understanding the motivation...

Mar1412 02:38 PM
bigfooted

11 
2,260 
Everybody knows one dimensional wave equation \frac{\partial^2u}{\partial t^2} = c^2 \frac{\partial^2u}{\partial x^2}...

Apr2710 09:06 AM
Hootenanny

1 
5,889 
\nabla^2 V = \nabla \cdot \nabla V.
Let me first break this down in English from my understanding:
\nabla V is...

Nov210 06:36 AM
MasterX

3 
4,439 
The definitions of a harmonic function u are: It has continuous 1st and 2nd derivatives and it satisfies \nabla^2 u =...

Aug310 08:18 PM
Mark44

10 
1,970 
F(s) = \frac{1}{K^s}
where K is a positive real.

Jun1310 05:10 PM
Count Iblis

3 
1,663 
im having problem integrating the equation
dydx=y^2/x^2
and also
dydx=3*y^2/x

Apr910 07:14 AM
StalkerM

2 
2,244 
What is the difference between simple fixed pole and simple movable pole?
Differential eqs. z(dw/dz)+w=0,...

Apr2011 08:03 AM
JJacquelin

1 
661 
For example, if y=x^2, then the derivative of y is 2x. We write the derivative as either f'(x)=2x or dy/dx=2x.
...

Dec2712 12:05 PM
HassanEE

5 
4,058 
On Wolfram Alpha it will offend give you a contour plot, and it has similarities to a bifurcation plot with respect to...

May1314 12:34 AM
alan2

2 
422 
How would you define what a coefficient is in the context of differential equations? How do they influence the graph...

Jul112 03:45 AM
chiro

1 
734 