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#26 Help Me ! » Probablilty Help » 2007-10-15 10:05:28

freddogtgj
Replies: 2

Hi people can anyone help me in this question:

Gonzo plays a series of independent games. At the start of each game he pays £1 then rolls a fair 6-sided die. If he obtains a 6 he receives £C; otherwise he receives nothing.  The game continue until he throws a 1, when the series of games stop.  Find the expected amount he wins and hence state the value of C for which the game is fair (the expected amount he wins is zero).

I'm thinking it has something to do with the Gamblers Ruin problem if you're familiar with it.

Thanks in advance

#28 Help Me ! » Linear Algebra- Square matrices » 2007-10-11 00:48:52

freddogtgj
Replies: 2

I have this question that's causing some confusion:
Let A and B be square matrices of the same size. Show that

(A+B)(A-B)=A²-B²

if and only if A and B commute.

#29 Help Me ! » Probability Generating Function » 2007-10-08 01:54:47

freddogtgj
Replies: 0

I have this question that I need help on:

Let X and Y be independent random variables each with Poisson distribution, with parameters (lamda) and (mue) respectively.  Show that Z=X + Y has Poisson distribution and state its parameter.  If X1, X2,...,Xn are independent identically distributed random variables, with common distribution which is Poisson with parameter (lamda), find the probability generating function of W= ∑ Xj and hence state the distribution of W.

#30 Re: Help Me ! » derivative » 2007-04-21 09:36:09

To prove that you have to use the formula:
sin(A±B)=sinAcosB ± cosAsinB

then you make A=B=x

#31 Re: Help Me ! » Integration Help » 2007-04-21 09:29:44

Oh yea the constant! Partial fractions? Well, yea, but depends on the question...

#32 Re: Help Me ! » Integration Help » 2007-04-17 04:50:06

Oh i see thanks!

The answer is: x-ln(1+x)
Am i right?

#33 Help Me ! » Integration Help » 2007-04-17 01:58:33

freddogtgj
Replies: 4

I can't believe I forgot this, but could someone explain to me how to solve the following integration:

∫x/(1+x) dx

#34 Re: Help Me ! » Algebra help needed » 2007-03-27 22:07:20

Wouldn't the elements be:
(123)          (123)          (123)
(123)          (132)          (213)         

(123)          (123)          (123)
(231)          (312)          (321)

#35 Re: Help Me ! » Algebra Help » 2007-03-21 23:45:40

Cool thanks! I have a similar answer using wikipedia
http://en.wikipedia.org/wiki/Boolean_ring

#36 Help Me ! » Algebra Help » 2007-03-20 21:03:28

freddogtgj
Replies: 2

I have this question that I need help in

Let R be a ring in which a^2 = a for all a ∈ R. By considering (a+b)^2,
show
(a) R is commutative;
(b) a+a = 0 for all a ∈ R.

Thanks in advance!

∈ - element of

#38 Help Me ! » Algebra Help » 2007-03-14 01:52:16

freddogtgj
Replies: 2

I have this question that I'm slightly stuck on:
Let R be a ring with identity. We say that two elements a and b of R are associates,
written a ~ b, if b = au for some unit u of R.
In the case that R = Z12, calculate the equivalence classes of ~

How do I go about answering this?
Thanks in advance

#39 Re: Help Me ! » Differential Equation Problem » 2007-03-12 22:16:39

Yes, but I'm not sure about the coefficients of cos and sin...I have to double check

#40 Re: Help Me ! » Differential Equation Problem » 2007-03-12 08:53:09

Brilliant website JaneFairfax and Stanley_Marsh I got something similar, but not exact

#41 Help Me ! » Differential Equation Problem » 2007-03-11 12:19:18

freddogtgj
Replies: 6

The question I'm having a problem with is:
16y'' + 8y' + 5y - 10x = 0,    y(0)=-2,  y'(0)=-1

I got half of it done, but I'm not sure whether I'm doing it right...can someone help me?

#42 Re: Help Me ! » Differential Equation » 2007-03-11 06:44:27

I agree with you as well but the question seems to be what i have typed out

#43 Re: Help Me ! » Differential Equation » 2007-03-11 04:26:32

I'm not sure if that applies to this question

#44 Re: Help Me ! » Differential Equation » 2007-03-10 22:19:22

I have another similar question this time, but it's proving too be a little bit more difficult:

y' + tan(x)y + x = 0,        y(0)=2

#46 Re: Help Me ! » What is 7+9? » 2007-03-10 11:44:42

lil_tomboysk8 wrote:

how is it 16 since there is no 9. 7 ate it. Is the answer no solution?

Didn't you ask the question in the first place?

#47 Re: Help Me ! » Differential Equation » 2007-03-10 11:24:53

If you don't mind checking my answer:

arctanh(y) = ln (x+1)

#48 Help Me ! » Differential Equation » 2007-03-10 11:11:44

freddogtgj
Replies: 12

I have this particular question which i'm having trouble with... could someone help me?

"Solve the following initial value problem
(1+x)y' + y^2 - 1 = 0,        y(0)=0"

Thanks in advance!

#49 Re: Help Me ! » help needed » 2007-03-07 23:23:38

There is no solution in Z19, Z17 has two solutions of 6 and 11.


Yea Ricky was right!

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