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

Feb2313 09:24 AM
micromass

1 
40,088 
Hello everyone,
I have recently bumped into the Kramers Kronig Relations while reviewing some of my Eletromagnetism...

T 08:48 PM
Zag

3 
94 

 
 
 
Say for some general function f(x), and g(x) = ∑x=0∞ f(x) (assuming function is defined)
Is there a way to find the...

T 03:30 PM
cmcraes

8 
137 
So I was doing my calc homework when I stumbled upon this thought:
lets say you were trying to find the solid of...

T 02:11 PM
SteamKing

1 
74 
Hi
I am facing a mathematical problem in my research. I am not a maths magor and i need to do this to move on with my...

T 12:58 PM
Aladdin123

22 
340 
I do not know how to formulate formulas on this forum so I just wrote it neatly on a piece of paper and linked it.
...

Y 07:21 PM
Mark44

1 
102 

 
 
 
How is this limit evaluated?
\lim_{k>0}\frac{sin(\pi k)}{sin(\frac{\pi k}{N})}
I know that it is N, but I...

Y 01:54 AM
JJacquelin

1 
239 
If exist a connection between the infinitesimal derivative and the discrete derivative $$d = \log(\Delta + 1)$$...

Apr1814 05:17 PM
Jhenrique

6 
136 
Hey guys, just trying to understand how the quotient rule is derived, so I head over to wikipedia and saw this:
...

Apr1814 02:14 PM
gomess

4 
134 
Hello,
I have a real world application that I need some help with. I am sensitive to the fact that this is not the...

Apr1814 01:12 PM
berkeman

2 
107 
Hello,
Wolfram is giving me the required answer however, the steps it uses I find very confusing. Can anyone share...

Apr1814 09:53 AM
Mark44

1 
147 
For my own use and consumption, I created a generalization of the nth integral of a function f and I'm posting it here...

Apr1814 03:03 AM
pwsnafu

5 
185 
Accidentally I wrote in the wolfram f(x) = f(1/x) the the wolfram give me the solution for this equation (f(x) =...

Apr1714 08:45 PM
Simon Bridge

11 
300 
Hi all, I'm working on some QFT and I've run into a stupid problem. I can't figure out why my two methods for...

Apr1714 01:51 PM
welcomeblack

2 
142 
Hello,
I've come across equations where people use the approximation
\int_0^1 \exp(f(x))\, dx \approx \exp \left(...

Apr1614 09:57 PM
welcomeblack

1 
154 
Hi
I am currently reading a book where this showed up:
The author gave a ##3## parameter equation (note ##Y##...

Apr1614 12:20 AM
Red_CCF

1 
335 
i'm trying to integrate this:
$$W=\frac{ε}{2}\int{\vec{∇}\cdot\vec{E})Vdτ}$$
where ε is a constant, E= ∇V, τ is...

Apr1514 09:35 PM
Simon Bridge

4 
236 
I am working on the derivation of the angular momentum squared operator (in quantum mech.) and there is one step that...

Apr1514 07:53 PM
hideelo

2 
136 
\int \frac{d}{dx}f(x)dx = f(x) + C_x \iint \frac{d^2}{dx^2}f(x)dx^2 = f(x) + xC_x + C_{xx}
\int...

Apr1514 02:48 PM
Mark44

7 
280 
Hey guys, I'm really really confused on how we come about the plane z = x  y. I always have been and it's proving to...

Apr1514 08:47 AM
HallsofIvy

2 
162 
I'm brushing up on calculus. I don't see how this derivative works.
x(t) = A cos(ωt  \varphi)
v(t) = dx / dt = ...

Apr1414 06:49 PM
jbunniii

1 
169 
I understand how to use it, but I'm just getting really confused on when you use it? Is there a way you can look at...

Apr1414 06:45 PM
Jhenrique

4 
271 
Hi!
I am having trouble following the derivation from Euler's Equation to Bernoulli's Equation. The trouble lies in...

Apr1414 01:38 PM
Einj

3 
245 
how do I find the derivative of tanh^1(sinh(2x))
do I just find derivative of tanh^1(x) this then substitute...

Apr1314 08:14 PM
AMenendez

2 
233 
please tell me if i did this correctly:
task: i'm trying to divide the differential dA by dV
where.. dA =...

Apr1314 03:57 PM
HallsofIvy

3 
203 
Hi all ! I'm new here :)
So I'm facing some confusions here regarding integration by parts. While surfing through...

Apr1314 01:10 AM
O.CModderz

9 
372 
the coordinates of cycloide are
##x= a (\theta sin \theta)##
##y= a(cos \theta 1)##
If i use ##\theta =\omega...

Apr1214 10:16 PM
Simon Bridge

3 
224 
A uniformly convergent sequence of continuous functions converges to a continuous function.
I have no problem with...

Apr1114 01:26 AM
GenePeer

5 
540 
Hello. My first time posting here. So... My question is kinda hard to explain but I will try to. So we all know about...

Apr914 02:00 PM
AlfredB

0 
235 
Hello,
Consider two particles which interact via a Gaussian potential:
V(\mathbf{x}) = \exp(\mathbf{x}^2)
I...

Apr914 11:08 AM
Irid

0 
194 
Hi,
I'm doing this integration:
I = ∫^{1}_{1}1/(\pi√1x2)dx
I made the substitution x = cosθ, and I'm fine...

Apr814 11:03 AM
jbunniii

1 
270 
I'm not sure which category this post actually belongs to, or if the title of this post is even accurate. I guessed...

Apr814 03:37 AM
micromass

19 
766 
So this is a theoretical question I am not sure about with partial derivatives.
Say we have function x(i,j) with ...

Apr814 01:33 AM
chicago77

2 
284 
hey pf!
i have a few question about the physical intuition for divergence, gradient, and curl. before asking, i'll...

Apr714 11:35 PM
joshmccraney

8 
358 
Is it necessary for some point ##x## of the function to be saddle that
##f'(x)=0##?

Apr714 04:34 PM
Mark44

3 
254 
I'm looking for a way to write down an analytic approximation for the following integral:
\int_0^\infty \frac{k...

Apr714 03:04 PM
csmallw

2 
296 
Hello all,
I have the following integration:
\int_{\infty}^{\infty}e^{j2\pi...

Apr714 02:23 PM
S_David

3 
331 
Function ##f(x)=x^4## has minimum at ##x=0##.
## f'(x)=4x^3##
##f'(0)=0##
##f''(x)=12x^2##
##f''(0)=0##...

Apr714 10:08 AM
HallsofIvy

2 
253 
I have been trying to follow how the complex Fourier coefficients are obtained; the reference I am using is at...

Apr614 05:08 PM
jellicorse

4 
272 