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## #1 Re: Introductions » Hi to everyone » 2009-05-03 05:12:54

hey bobby and thank you!

## #2 Re: Help Me ! » equivalence Relations-equivalence classes of related elements » 2009-05-03 05:11:30

Thank you... At first i didnt get it but it makes more sense now that i got a good nights rest and read what you posted.

## #3 Re: Introductions » Hi to everyone » 2009-05-02 06:04:30

Hey everyone! Names Tony, and yes you can cal me Tone(beep beep). I'm sorry for not introducing myself in my previous posts, but i am under pressure getting this "should-be-simple" discrete structures with all my other finals coming up. I am a new member and I have read previous posts from other members that helped tremendously! I have completed up to calc one and preceeding math classes (trig, algebra "of course", applied). I am enrolled for summer calc 2 so I am sure I'll be exercising my mind routinely on here! I am a CompSci major with a double minor.

## #4 Help Me ! » Digraph Relations » 2009-05-02 05:50:24

ToneMU84
Replies: 0

I am working on another type problem which wants us to list all the paths of length 2. I definantly know how to do that. I am stuck on the part is wants us to give the matrix for R^2.
Here is the problem and what i have.

abc, bcc, bcd,ccc,ccd,cda,dab  <----this is 100% correct on the length 2. so if you could visualize the digraph where a,b,c,d all relate in a clockwise direction with c being reflexive.
Where do i begin to make a matrix for this? I know I can get R^2 of course if i know R-matrix.

Thank You Sincerely,

Tony:)

## #5 Help Me ! » equivalence Relations-equivalence classes of related elements » 2009-05-02 05:43:53

ToneMU84
Replies: 5

I am currently in discrete structures and i understand transitive, reflexive and anti-symmetric propteries. I am currently stuck on a type problem that will be on my exam on Equivalence Relations
Here is the problem i am currently studying...

Suppsoe R is an equivalance relation {1,2,3,4,5}  What are the equivalence classes of each of the related elements.

1)1 is not related to 2
2)3R5
3)4R2
4)1 is not related to 3
5)3 is not related to 4

I know the answer b/c i have it in front of me, but dont understand y?!
Please if anyone could explain why the equivalence classes  are {1} {2,4}{3,5} which would project the data I provided above.

Knowing my properties, i think since!?!  1 is not related to 2, and 1 is not related to 3, 1 has to reflexive? related to itself?
Since nothing relates to 3 and 3 only relates to  5, our equivalence class has to be {3,5}?!?
{2,4} i wouldnt know where to being.
I wish i could better visualize this as a digraph i think it would help me a lot more, but I cant plot this information correctly,

Thank You Sincerely,

Tony