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

Feb2313 09:24 AM
micromass

1 
46,176 
For this function
y=\sqrt{2ln(x)+1}
if I use the chain rule properly, should I be getting this answer?
...

T 12:34 AM
Shyan

1 
85 
Can someone explain to me why in this equation (attached)
where ρ(t)=\sumδ(tti) , dirac funtion.
in the left...

Y 10:03 PM
Fredrik

3 
157 
First off: I think I understand the chain rule and how it derives from
\lim_{h \to 0} \frac{ f(x+h)f(x)}{h}
...

Y 07:55 PM
Fredrik

8 
163 
Hi
The question is the following: is it possible for a (say) real function to be continuous at a certain point...

Y 08:42 AM
glance

4 
136 
Hi :)
I'm doing my ALevels and have a maths investigation project for which I decided to model the working of a...

Aug2514 07:58 PM
Simon Bridge

10 
434 
I was playing around with some simple differential equations earlier and I discovered something cool (at least for...

Aug2514 12:42 PM
gopher_p

3 
195 
Hi,
Is the following integral well defined? If it is, then what does it evaluate to?
\int_{1}^{1} \delta(x)...

Aug2514 03:55 AM
pwsnafu

10 
243 
I am looking at a solution to an question and I don't understand how the value of the following definite integral...

Aug2414 05:29 PM
SteamKing

7 
245 
Hi. Is using the LeviCivita symbol to calculate crossproduct combos like A x (B x C) allot faster than just using...

Aug2414 10:50 AM
Fredrik

2 
155 
I'm doing an undergraduate course in engineering 1st sem. I have physics which contains cumbersome amount of vector...

Aug2314 06:59 AM
mal4mac

2 
179 
Firstly, the set E is defined:
"Let E be the set of all positive real numbers t such that tn<x."
Later on the...

Aug2214 12:51 PM
GMB

3 
1,616 
many books only tell the operation of total derivative and partial derivative,
so i now confuse the application of...

Aug2114 08:11 AM
HallsofIvy

3 
324 
Hey. I'm new to the forum and I was hoping you could help me solve this integral. I was searching for a clue on...

Aug2114 06:36 AM
Wort

6 
236 
Differentiation by first principles is as followed:
$$y'=\lim_{h\rightarrow 0}\dfrac {f\left( x+h\right) f\left(...

Aug2014 10:23 PM
FilupSmith

15 
2,368 
Apparently,
f \nabla^2 f = \nabla \cdot f \nabla f  \nabla f \cdot \nabla f
where f is a scalar function.
...

Aug2014 12:12 PM
vtfjg87

2 
189 
Let a\in\mathbb{R}, a>0 be fixed. We define a mapping
\mathbb{Q}\to\mathbb{R},\quad q\mapsto a^q
by setting...

Aug1914 06:20 PM
jostpuur

2 
186 
Hey guys,
Not claiming to be an expert on numerical methods here but I am doing some digital integration using...

Aug1914 01:46 PM
HallsofIvy

1 
171 
I'm an undergrad who has just completed the standard calculus sequence (1, 2, and multivariable). I've done well in...

Aug1814 02:04 PM
Matterwave

3 
294 
You can prove if f(x) is an odd function and f(x+ t) is an even function then f(x) is periodic with period at most 4t....

Aug1714 02:10 AM
dimitri151

2 
228 
I think this is a theorem, and I'm telling myself that I've proved it. Just a shout out for any possible...

Aug1614 11:39 PM
WWGD

3 
235 
1.
What if absolute convergence test gives the result of 'inconclusive' for a given power series?
We need to...

Aug1614 03:26 PM
mathman

5 
351 
Simply put, can you find the function which extremizes the integral
J=\iint L\left(x,y,f(x),f(y),f'(x),f'(y)\right)...

Aug1614 03:36 AM
julian

4 
410 
Can you suggest a general analytical solution to the following equation
\ln(x^{3/2})bxc=0
where x is real...

Aug1514 02:54 PM
Borek

6 
305 
Hello everyone,
I brushing up on integration techniques and I came across this problem in a book. Does anyone here...

Aug1514 01:43 PM
FeynmanIsCool

2 
392 
Could someone walk me through how to maximize this 2variable function wrt z?
...

Aug1514 01:20 PM
da_nang

3 
337 
Hi,
Let y= sin(x) + cos(x) + tan(x) + sec(x) + csc(x) + cot(x)
Find the minimum value of "y" for all real...

Aug1514 10:09 AM
Amad27

27 
781 
Hi,
I am struggling for some time to solve the following integral:
$$
\int_{n}^{Nn} \left(...

Aug1414 11:13 AM
divB

0 
200 
Our integral
\int\limits_0^{\pi/2} \sin^{2a+1}(x)\,dx
Has a Factorial Form:
{(2^a a!)}^2 \over (2a+1)!
What...

Aug1314 07:46 PM
musik132

3 
242 
I'm trying to work out the equation of a curve through 5 very specific points... these points are
(47.5, 46.3)...

Aug1314 12:31 PM
JJacquelin

5 
306 
Hi all,
I have this integral, and I wish to write it in a closedform in order to be able to program it. The...

Aug1214 07:52 PM
D H

4 
360 
I am looking for a good and easy access reference on multivariable calculus of variation with many examples and...

Aug1114 02:10 PM
verty

1 
311 
Is there a nonzero continuous function, f, R > R such that ∫f(x) dx over (c, c^2+1) = 0, for all c in R? Hope this...

Aug1114 09:46 AM
disregardthat

3 
292 
I have read that even the simplest integrals (like y=x2) might need some correction if we want to reach an extreme...

Aug1014 03:41 PM
MrAnchovy

5 
370 
We know that in order to be integrated a function must be continuous.
Does this imply that space and time must be a...

Aug1014 07:41 AM
HallsofIvy

8 
354 
Hi guys,
I'm on the verge of sandwiching this particular sequence but I need rather tight upper estimate to trap...

Aug1014 06:53 AM
Seydlitz

4 
327 
Is there a rational function,not series, that approximates e^x
?
for example (x+1)/(x+3)

Aug914 05:54 PM
lurflurf

6 
458 
Ok for the purpose of this question let's stick to the flux integral:
The general formula is ∫∫s...

Aug914 03:13 PM
davidbenari

4 
356 
So, is there anyway to make the dot product change linearly? What I mean by this is when the angle is 45 degrees, I...

Aug914 01:13 AM
Student100

5 
364 
Hi
How to estimate the asymptotic behavior of this function?
f(x)=\sum_{k=1}^{x}\log(k)
I mean, a closed form...

Aug814 08:03 AM
micromass

3 
353 
Hi there, I'm having some difficulty in understanding how the change of variables by considering a retarded time frame...

Aug714 05:36 AM
test1234

2 
253 