Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#1 Re: Help Me ! » Uniform Distribution / Conditional Probability » 2010-04-21 10:26:56

P.S. I used this site:

http://cnx.org/content/m16819/latest/

Example 2, Problem 3.

#2 Help Me ! » Uniform Distribution / Conditional Probability » 2010-04-20 17:55:11

ziggs
Replies: 2

So I just took a probability test and I'm having a hard time with the fact that my answer is wrong. I've done some research online and I believe I am correct, I was hoping to get some input. I'm new to using LaTeX so sorry if it's sloppy. Thanks!

Problem: Suppose that the amount of time in minutes that I wait for a bus is uniformly distributed on the interval [0,60].

(I got part A correct)
Part A: What is the probability I have to wait for at least 20 minutes?

Solution:

(I got part B wrong)
Part B: Suppose that when I arrive at the bus stop, I meet someone else who has already been waiting for the same bus for 20 minutes. If I take that information into account, what is the probability that I will have to wait for at least 20 minutes?

Solution:

Since someone else has already been waiting for the same bus for 20 minutes and has not been picked up yet, I would think we could change the sample space? So I used an interval of length 40, since the original was 60.

#3 Help Me ! » Fourier Transform Applied to NMR » 2010-02-27 09:45:12

ziggs
Replies: 0

Hi, I'm taking a Chemistry NMR & MRI class and were going over the part where the time domain graph is converted to the frequency domain graph by way of the Fourier Transform. I took Applied Mathematics last semester and we spent a week on the Fourier Transform but no time on the Fourier sine or cosine transform.

From what I can tell, all periodic functions can be described as a sum of sine and cosine functions. The Fourier Transform of this can be divided into a real and imaginary part.

Does anyone have an example or two of say an expression before and after? And if possible a graph before and after? Like which part is the real and which the imaginary? If I'm wrong somewhere here I apologize and let me know please.

Thanks for any input!

#5 Help Me ! » Diff EQ » 2009-09-08 12:23:06

ziggs
Replies: 2

I have 2 boundary value problems to solve. The first I think i have.

a).  y'' = 3x^2 , y(0) = 0, y(1) = 0   [ y'' being the 2nd derivative]

Integrating this twice yields y = (1/4)x^4 + Cx + D
then using the initial conditions we get y = (1/4)x^4 + (3/4)x

b). y'' - 4y = 1, y(0) = 1, y(1) = 1

From here is where I could use some guidance please. Thanks.

#6 Re: Help Me ! » Paper on Compact Sets » 2009-04-30 15:23:22

First off thanks for responding much appreciated. This is for a real analysis course. I have the Heine-Borel theorem and the theorem's within it. And a few relating to nested sequences and continuity over compact sets. The continuity seems more important. I also see that the Cantor Set is an example. The topic is on Compact Sets, I'm not sure how far i'm allowed to drift off.

#7 Help Me ! » Paper on Compact Sets » 2009-04-30 03:07:55

ziggs
Replies: 5

Hi guys, Was just hoping I could get a little insight from everyone :-)
I'm writing a paper on compact sets and have found a lot of useful theorems and definitions and such,
but need some more interesting or other useful stuff in there.
Was wondering if anyone knew some other theorems or maybe even real life things that rely on the compact sets?
Thanks for any help in advance!

Board footer

Powered by FluxBB