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

Feb2313 09:25 AM
micromass

1 
32,541 
how do we prove in set theory that ,nothing contains everything

May1811 08:46 AM
xxxx0xxxx

31 
4,797 
I'd like to test my understanding of some basic definitions using the example of a double coin toss. I think this...

May1811 07:00 AM
Rasalhague

8 
1,864 
Hello.
I have understood the Kuratowski definition of the ordered pair and appreciate it's usefulness but have a...

May1711 11:51 PM
xxxx0xxxx

4 
1,635 
I find the probability theory I'm doing in college very difficult until I start wording it all out in my head. If I...

May1711 11:40 PM
bpet

2 
1,018 
I have some more questions...
1) How do I exactly define an equivalence relation? I know it needs to be reflexive,...

May1711 10:18 PM
xxxx0xxxx

6 
1,474 
I recently read about the unexpected hanging problem and I was so surprised that logic actually failed in determining...

May1711 07:17 PM
xxxx0xxxx

15 
2,458 
Or is it too circular?
A = {x  x \in A}

May1711 04:35 PM
Hurkyl

3 
1,257 
How can I find the correlation length of an autocorrelation?
Is it the distance to the first zero of the...

May1711 02:07 PM
Shaddyab

0 
1,343 
Suppose X is a uniformly distributed random variable on an interval for some real a.
Let Y=X^2. Then what could you...

May1711 02:04 PM
micromass

1 
5,964 
Maybe someone is really good with stats, or has access to a statistics professor. Here we go:
I am trying to...

May1611 12:22 PM
Stephen Tashi

2 
2,210 
algebra 2 combinations

May1511 05:23 PM
phinds

2 
1,236 
could anyone explain to me that why:
let u=E. then E=E?
I am a bit confused. Thanks.

May1511 03:21 PM
mathman

3 
743 
I have a problem, but don't know which way to try to solve it.
There is lottery: 3 numbers will be drawn out of...

May1511 03:15 PM
mathman

5 
2,573 
Hey guys,
Anyone here familiar with blackjack mathematics? I came across a series of threads at another forum where...

May1411 03:48 PM
Pengwuino

5 
3,916 
According to wiki:
"a nonabelian group, also sometimes called a noncommutative group, is a group (G, * ) in which...

May1411 12:36 PM
bentley4

6 
1,328 
I am unsure what is meant by binary operation.
Is the binary operation of addition : addition and subtraction or is...

May1411 12:32 PM
Fredrik

12 
2,400 
A set is defined as a collection of 'objects'. Does there exist something that is not considered an object in...

May1411 10:20 AM
micromass

21 
2,222 
In the presentation of survey results, there are some questions wherein some of the respondents did not indicate...

May1311 10:55 PM
safina

0 
858 
Hi
Can anyone help me with the following question from a past paper I am working through?...

May1311 02:24 PM
micromass

6 
929 
I came across this question:
http://imageshack.us/m/3/4510/axiomsq.png
which I'm confused about. I know what the...

May1311 12:56 PM
I like Serena

13 
2,643 
Just something I've been wondering, the probability that the top half of a ladder in a national sport will have...

May1311 04:09 AM
chiro

7 
1,407 
The question is "An experiment in which a dice is tossed twice. Let X be the random variable defined by recording the...

May1211 10:04 PM
bpet

3 
2,422 
So suppose we have 3 boxes, A,B,C. Black and Red balls in each.
In A, 3R and 7B.
B, 6R and 4B
C, 8R and 2B
First...

May1211 11:34 AM
monomath

1 
1,103 
Hello friends,
I have this problem it reads:
A random variable X is defined to be the larger of the two values...

May1211 05:15 AM
Iclaudius

4 
772 
Hey all,
Here's a nice Wednesday afternoon brain test for you all (I've been pulling my hair out with this one,...

May1211 12:19 AM
Stephen Tashi

1 
745 
Is the number of points/cardinality in R^2 greater than R, or are they equal?
if they are equal, how does one...

May1111 10:33 PM
disregardthat

13 
3,776 
Hello, I have just been reading about the ZermeloFrankel (ZF) axioms for set theory and thinking about their...

May1111 09:42 PM
Hurkyl

7 
1,813 
Hi,
If I have a joint probability mass function p_{X,Y}(x,y), can we get the marginal probability mass functions...

May1111 05:13 PM
S_David

10 
2,950 
I'm browsing around waiting for my books to arrive, and I came across this (PDF) site that says \forall x P(x)...

May1111 01:47 PM
xxxx0xxxx

6 
9,352 
I've been given the question:
In a photographic process, the developing time of prints may be looked upon as
a...

May1011 06:19 PM
mathman

1 
1,432 
I have a question. Let's say I wanted to estimate the median income of all adults in my church. So I randomly select...

May1011 06:02 PM
zli034

1 
1,027 
Hi,
Suppose that an ndimensional vector \mathbf{z}=\begin{pmatrix}z_1&z_2&\cdots & z_n\end{pmatrix}^T is...

May1011 09:54 AM
S_David

8 
5,199 
Consider the Uniform distribution (continuous) U(1,1) which has p.d.f. f(x) = 1/2 for 1 < x < 1 and 0 otherwise.
...

May911 10:16 PM
bpet

2 
1,889 
Give an example to show that if not assuming independence of X1, X2, ..., Xn it is possible to show that Var(1/n * sum...

May911 03:22 PM
squenshl

2 
766 
Hi all,
http://www.physicsforums.com/attachment.php?attachmentid=35247&stc=1&d=1304691641
In this question, I...

May911 10:53 AM
Stephen Tashi

2 
700 
Wrong thread.

May811 10:27 PM
squenshl

0 
447 
Hi, i have a couple of problems that im not sure about (i get the wrong answer for particular cases because the...

May811 08:27 PM
bpet

28 
6,955 
In how many ways can obtain polynomial from
http://im3.gulfup.com/20110505/1304543619801.gif
notes that c any...

May811 02:49 PM
matiasmorant

1 
718 
Hi everyone!
I really need your help if you are good in time series. I have a problem on moving average...

May711 11:49 PM
Stephen Tashi

1 
840 
I am trying to compare two groups (for statistical significance), a control and a treatment group across more than one...

May711 07:49 PM
Stephen Tashi

1 
2,877 