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## #1 Re: Help Me ! » Help please » 2013-01-03 01:22:25

Sorry it has been a while since I have done any proper maths.  Could you provide the solution please?

## #2 Help Me ! » Help please » 2013-01-02 21:22:20

freddogtgj
Replies: 4

Hi, I would like your help in proving the following:

## #3 Help Me ! » Differentiation Problem » 2011-02-06 03:50:47

freddogtgj
Replies: 5

Hi all,

I need help answering a question that I am having trouble with.  I think it has to do with differentiation, but not too sure.

Question

A farmer wants to put up a fence around a rectangular pen with an area of 128m^2.

One side of the rectangle is a wall, what is the least length of fence needed to cover the perimeter left?

I hope I covered everything in the question.

freddogtgj
Replies: 1

## #5 Help Me ! » How do you solve this? » 2009-02-07 04:14:19

freddogtgj
Replies: 2

I'm having trouble with this question, can you help?

Need to find n.

## #6 Help Me ! » Anyone familiar with the Kauffman Bracket? » 2009-01-26 01:17:53

freddogtgj
Replies: 0

Here is the question regarding the Kauffman bracket:

Explain why rule 3 for the Kauffman bracket applies whenever a disjoint unknot
(i.e. an unknot with no crossings with other parts of the diagram) appears in the
diagram, not only if it is outside the rest of the diagram.

## #7 Re: Help Me ! » Algorithmic Graph Theory Help » 2009-01-14 08:22:48

Ok i see mathsmypassion.  Now does that mean the number of edges are 12?

## #8 Re: Help Me ! » Algorithmic Graph Theory Help » 2009-01-12 01:46:06

Well, the stumbling block for me is the vertex part.  I'm not quite sure how the vertex points are meant to be read.  It says that the set consists of all triples with each x_i equal to 0 or 1, but i thought that a vertex can only be defined by one x_i rather than a triple.  Am i wrong?

## #9 Help Me ! » Algorithmic Graph Theory Help » 2009-01-11 08:18:52

freddogtgj
Replies: 5

Consider the graph G defined as follows.  The vertex set V(G) consists of all triples

with each
equal to 0 or 1.  The edge set E(G) consists of all pairs of triples
such that there is exactly one number i with
.

How many vertices does G have? How many edges does G have?

Sorry for the maths looking like superscript compared to the rest of the text.  Anyone like to tell me how to deal with that will also be great.

## #10 Re: Help Me ! » Linear Algebra Help » 2008-10-02 11:26:41

I think JaneFairfax is going about this the right way because Ricky I don't think I can give you an answer to that question you are asking except that there are n elements in X that can be mapped to m elements in Y.

## #11 Re: Help Me ! » Linear Algebra Help » 2008-10-01 23:14:16

Anyone any ideas?

## #12 Re: Help Me ! » Linear Algebra Help » 2008-10-01 21:06:44

I understand what you are saying about mapping, but I'm afraid that's all there is to that question.

## #13 Re: Help Me ! » Linear Algebra Help » 2008-10-01 09:03:10

That's the thing I'm not too sure.  I thought it had something to do with the values n and m.  I assume n suggests that there are n values in the set X and m values in set Y, then from there we find out how many functions could be mapped.  Does that help or was that load of b*ll**ks!

## #14 Help Me ! » Linear Algebra Help » 2008-10-01 03:18:28

freddogtgj
Replies: 10

I'm not quite sure how to answer this question:

Let X and Y be sets with

and
.

Determine the number of functions f mapping X into Y.

## #15 Re: Help Me ! » Make y as the sunject... » 2008-02-18 10:48:19

of course...we have an equation of a circle in there as well!

## #16 Re: Help Me ! » Integral question » 2008-02-17 12:20:36

does anyone else get 0?

## #17 Help Me ! » Make y as the sunject... » 2008-02-17 11:51:52

freddogtgj
Replies: 6

I need to make y as the subject of the following question:

Any suggestions?

## #18 Help Me ! » Differentiation Help » 2008-01-27 00:31:48

freddogtgj
Replies: 1

Hi there I saw this question and got stuck, could someone tell me how can I solve this:

Find the differential of:

## #19 Help Me ! » Stats Help Needed! » 2008-01-21 02:33:17

freddogtgj
Replies: 1

Consider the birth of twins. Let Φ denote the probability that they are identical, in
which case they must be of the same gender. If they are fraternal, that is, not identical
twins, each child is equally likely to be male or female independently of the other child.

(a) Justify the result that
P(twins are of the same gender) =

(b) Let Y be the number of pairs of twins of the same gender out of m pairs of twins.
Then Y has a binomial distribution with parameters m and (1+Φ)/2. Write down the
likelihood for the single observation y of Y .

## #20 Re: Help Me ! » Linear Algebra » 2007-12-13 23:59:46

No idea! What kind of question is this?!

## #21 Help Me ! » Linear Algebra » 2007-11-29 23:45:48

freddogtgj
Replies: 1

Question that is posing a problem is:

Determine which of the following are linear transformations from P_2 to P_2:

(a) (L(p))(t)=t+p(t)

(b) (L(p))(t)=tp'(t)+p''(t)

## #22 Help Me ! » Linear Algebra help needed! » 2007-11-22 08:42:26

freddogtgj
Replies: 1

Here's the question:
Consider the following vectors in R³:

Show that

are ordered bases for R³.

## #23 Re: Help Me ! » computing integral » 2007-11-22 08:00:37

Can you not just expand the bracket so you are left with

and then use the rule for integrating e?

## #24 Help Me ! » Linear Algebra Help Needed! » 2007-11-15 09:56:53

freddogtgj
Replies: 1

Hi this is the question that's troubling me:

Show the following

(a) If

is a spanning set for a vector space V and v is any vector in V, then
are linearly dependent.

(b) If

are linearly independent vectors in a vector space V, then
cannot span V.