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

Feb2313 09:24 AM
micromass

1 
46,040 
i'm battling unsuccessfully to find a delta epsilon proof for continuity of exponential function.
this is what i've...

May2611 09:19 PM
dimitri151

23 
5,230 
I know the derivative is cosx but I don't know what to do.
So I get the derivative of sinx down to:...

May2611 09:17 PM
iRaid

3 
901 
I'm trying to evaluate the derivative of the Riemann zeta function at the origin, \zeta'(0), starting from its...

May2611 07:45 PM
TriTertButoxy

7 
2,697 
given the function
arg\xi(1/2+is)
is this an increasing function of 's' ?? , i mean if its derivative is...

May2611 05:05 PM
henry_m

1 
797 
This is not a bookquestion by far. It does have a nice solution, but I am stumpled on how to get it
...

May2611 08:27 AM
Nebuchadnezza

5 
951 
There the well known theorem that every open set (I'm talking about R here with standard topology) is the union of...

May2511 09:03 PM
dimitri151

6 
3,316 
1) Fact: Let X be a metric space. Then the set X is open in X.
Also, the empty set is open in X.
Why??
2)...

May2511 03:11 PM
jbunniii

10 
5,407 
Hi, I want to know if there's a general method of changing variables of a function and reduce the original number of...

May2511 02:45 PM
Jaynte

1 
877 
Hi, this is a very basic question. I want to know why are implicit functions used, when the purpose of functions is to...

May2511 02:15 PM
Tosh5457

10 
2,162 
I hope this is the right place to post this question. I saw this equation on a car's back windshield. I don't know...

May2511 11:17 AM
arildno

3 
719 
Fix some constant 0<\alpha \leq 1, and denote the floor function by x\mapsto . The conjecture is that there exists a...

May2511 07:44 AM
micromass

3 
1,190 
I consider an array of lattice points and construct a vector at each lattice points.
How to convert this discrete...

May2511 12:40 AM
saravanan13

2 
934 
In the Tsiolkovsky rocket equation derivation there is a part that says:
\frac{dV}{dt} = \upsilon_e \frac{1}{m}...

May2411 07:36 PM
LogicalTime

6 
2,773 
Nevermind I figured it out ec{w}?

May2411 07:20 PM
Gebraroest

0 
568 
Ok,
So i have a problem understanding conflicting results of a derivative,
Consider the derivative of x2, which is...

May2411 06:19 PM
gb7nash

4 
1,397 
I am trying to calculate the following integral
I=\int_0^\infty\frac{x}{(x+ia)^2}...

May2411 12:21 PM
JJacquelin

14 
2,152 
\int_{\infty}^{+\infty}\frac{e^{x^2}}{\sqrt{x^2+1}}dx
I calculated it numerically, but I need an exact number....

May2411 09:54 AM
DivisionByZro

3 
1,012 
Hi guys,
I've been doing past paper questions for an exam and I've gotten stuck with the limits of an integral. We...

May2411 08:21 AM
tinytim

5 
910 
As well known, for any topological space (X,T), there is a smallest measurable space (X,M) such that T\subset M. We...

May2311 06:29 PM
linulysses

9 
1,682 
So I've just completed my high school calculus course (just introductory calculus) and I loved it. In fact I got 100%...

May2311 06:22 PM
micromass

4 
540 
Kind of stuck (embarrassingly) on determining what poles of the function:
1/(z^6 + 1)
lie above the y axis (I'm...

May2211 09:09 PM
SteamKing

3 
1,482 
I'm a bit lost on this part of my course (ODE's and complex analysis). We've only done about 23 of these (seemingly...

May2211 03:16 PM
kru_

1 
1,286 
Hey guys
I've been reading through a few books and I can't seem to work this out;
\int _0^{\infty }e^{a x^2}xdx =...

May2211 11:21 AM
genericusrnme

2 
548 
Hi,
I am an engineering student and I have so far taken Calc 1 & 2 and Ordinary differential equations. I need some...

May2211 09:19 AM
3.1415926535

12 
1,728 
Hi guys, I am reading a proof on Holder's inequality. There is a line I don't understand.
Here is the extract from...

May2211 03:32 AM
henry_m

1 
1,957 
The following is from my investigation of a problem for my math term paper.
An object is given a certain linear...

May2111 07:33 PM
HallsofIvy

1 
1,090 
The function u(x,t) satisfies the advection equation \frac{ \partial u}{ \partial t}0,5\frac{ \partial u}{ \partial...

May2111 12:26 PM
jacyny123

0 
1,202 
If I put these 2 lines in to wolframalpha.com it comes up with a solution
x = 1 + 2t , y = 2 – t , z = t ; x = 2...

May2111 11:41 AM
paulfr

2 
739 
at the serie \sum_0^{\infty} a_n (x  c)^n , the radius of convergency is:
.
R= \lim_{n \to \infty }...

May2111 04:33 AM
3.1415926535

5 
959 
I'm working on this differential equation this few days.... Could you give
some guidance on approximate solutions to...

May2011 09:08 PM
albertshx

3 
960 
Does a derivative exist at a vertical asymptote of a function?
For the function 1/(x^2), there is a vertical...

May2011 05:26 PM
HallsofIvy

3 
760 
Something has been bugging as of late: usually, derivatives (ordinary and partial) are defined for interior points....

May2011 04:37 PM
ToffeeC

7 
1,800 
I want to use a Kalman filter to estimate the motion of an object. However, the catch is, the measurements I have only...

May2011 04:07 PM
chingkui

1 
715 
It is known that T in Hom(V) is selfadjoint if (Ta,b)=(a,Tb)
Let \theta be the isomorphism from V to V*, then (Ta,...

May2011 01:26 PM
yifli

0 
505 
Hello all,
I am reading an engineering book and am having trouble understanding a bit. Let u, v and w be...

May2011 11:29 AM
pamparana

4 
739 
If f : Rn > R is Lebesgue measurable on Rn, prove that the function F : Rn * Rn > R defined by F(x, y) = f(x  y)...

May2011 09:48 AM
Eynstone

3 
1,297 
In a book I'm reading, it says:
If beta is orthogonal to the set A, then beta is orthogonal to the closure of the...

May2011 08:26 AM
micromass

4 
1,024 
Most of the time I can visualise whether some solids of revolution are annulous or not but sometimes I just don't see...

May2011 07:04 AM
kr73114

4 
1,184 
How do I find the Laurent expansion of a function containing the principal branch cut of the nth root?
Example:...

May2011 06:59 AM
HallsofIvy

4 
2,066 
I understand that the limit of the sum of two sequences equals the sum of the sequences' limis: \displaysyle...

May2011 01:32 AM
dimitri151

6 
5,885 