Math Forum / Mathematics / Undergraduate Math / October 2005

A set has 2^n subsets. For this reason we can make 2^n
different sums of events ( one of those events is also
impossible event N ) from sample space containing n
elementary events

I don't get this whole concept of events being treated as sets
G ... certain event
1. Sum of events  (A U B) happens if either of both events occur
- Is sum of events also an event ?

I'm having problems with a couple of limits.
#1: lim as x -> +infinity of (sqrt(x^2-x)-x)
  I solved it like this:  (.5(x^2-x)^-.5 (2x-1)) -1
                         =(2x-1/(2sqrt(x^2-x)) -1

I'm trying to solve this problem:
There's prime p>3 and positive integers a,b,c that:
a+b+c=p+1 and:
a^3+b^3+c^3-1 can be divided by p.

Its a very basic question but I'm left very confused because I have a feeling the answer is not as obvious as it first seems. The question,
"How many anagrams of 'BIRMINGHAM' contain the sub-word 'MAN'?"
The obvious answer is 8!/(2!*2!), but if 'MAN' is treated as one letter, how ...

need some help to prove that Z(Sn)=1 for all n >,= 3

I'm a self-taught programmer, and I have nothing more than High-School
algebra under my belt, so cut me a little slack :)
I am tring to make a function for a program that will take the
following data: AngleX, AngleY, AngleZ, and RayLength.

how to plot the irrational number pi on a number line. i know the procedure for square roots of differant non-perfecr square number. it is by drawing a perpendicular at a suitable integral lenght again o suitable integral lenght such that the hypotenuse is of required length as ...

Hi, i am an university student in Turkey. My major is math. I AM SOOO CONFUSED. I did search on the internet and at the library of our university. But would not find the correct, precise answer. You may be as abstract as you want! Thanks a lot.
Q1-Let f be a function defined by ...

I have a quick Discreet Question on strong induction
the question is "Prove by stron induction that postage of 24 cents or
more can be achieved by using only 5-cent and 7-cent stamps."
I am totally baffled by this question I've worked on it for a bit and

i have been reading about the 'cholesky algorithm' to perform a cholesky
decomposition, here at :-
http://en.wikipedia.org/wiki/Choleskey_decomposition#The_Cholesky_algorithm
but under the section titled 'cholesky algorithm' and under where it says

Hi. Need help on the following:
Let Y be a subset of X; let X and Y be connected. Show that if A and B form a separation of X-Y, then YUA is connected.
If we assume that YUA is not connected, then we can write YUA as YUA = TUV for separated sets T and V. Then X = (TUV)UB. Now, I ...

  If I draw a random graph: specify the x-y intercepts,visually
estimate the derivate at several points, and note concavity how would I
convert this to function form?

I have a quick Discrete Question on strong induction
the question is "Prove by stron induction that postage of 24 cents or
more can be achieved by using only 5-cent and 7-cent stamps."
I am totally baffled by this question I've worked on it for a bit and

I really hope you can offer me some help cos I'm stuck
**If a set has elements A,B,C,D then the number of
subsets each containing 3 elements is
 4!/( (4-3) * 3! ) = 4