Math 224

[John]

Ok, I don't know anyone in my class and was looking for a little help and decided to ask here. Is anyone else in Dr. Wu's Discrete Mathematics 224 that meets MW @ 1:30 and working on the homework? On the fourth question, it refers to some "table 2." I was just wondering if anyone know what he was talking about or if they just wrote out all 101 numbers?

Thanks,
John

[Shaun Martin]

Table 2 can be found on page 232.  His chapter two stuff is actually our chapter three material.  Section 3.2 covers almost all of the homework problems.

[John]

Ok, thanks. For part 5.b, did you write out all 100 items?

[Shaun Martin]

No, I basically said that for every time i is an odd number, the answer is -1 and every time it's an even number, the answer is 1.  Nice to know that there's nothing in our book about products...

[pikapp886]

Does anyone know if we have a quiz today (9/13)? If so, what about?

[John]

Our syllabis (sp?) says so, and, not to sound too much like an ass, I imagine its over what we covered so far. There will probably be a truth table, DeMorgan's Law (probably not), domains, ranges, functions, ceiling, floor, unions, intersections, vector multiplication, Big Oh (or whatever), or proofs. I doubt he will quiz us over all that, but I also doubt he will mention anything that isn't in that list. Judging from our homework, it probably won't be that hard.

[Geoff Schreiber]

Phoenix wrote:
I doubt he will quiz us over all that, but I also doubt he will mention anything that isn't in that list. Judging from our homework, it probably won't be that hard.

You don't know Dr. Wu very well yet... Don't ever assume ANYTHING...

[John]

I was just wondering when the latest homework he assigned is due. The sheet says October 17, but I remember he changed it but not to when. Was it today or Wednesday?

Thanks,
John

[Shaun Martin]

I couldn't remember what he changed it to so I'm just going to try and finish it by classtime today.

[John]

I just talked to someone else and they said it was due Wednesday. Does anyone know what chapter we are on or where we can get these proofs? Are they done by induction?

Thanks,
John

[pikapp886]

Anybody have the problem he decided to assign us?  I seemed to have lost it.  Also appreciated would be a hint as to where I can find the technique to solve it.

[John]

Did anyone find an answer to Problem 3 homework 7? Can anyone give me any suggestions? Also, when doing the directed mapping from the matrix, how do you know which way the arrows point? For this example:

       a    b

a      0    1
b      0    2

Would this say 'a' points to 'b' once and 'b' points to 'b' twice OR 'a' doesn't point to anything and 'b' points to 'a' once and itself twice?

Thanks,
John

[pikapp886]

I did it as follows (similar to your first technique):
--a b c
a 0 1 0
b 1 0 1
c 0 1 2
a only points to b
b points to a and c
c points to b and to itself (twice).

[John]

Thanks, but you chose the only one of the three that gives the same result no matter how you did it. :) Oh well though, I'll just see what he says.

[pikapp886]

these are directional graphs (with directional arrows)
--a b c d
a 1 1 1 0
b 0 0 1 0
c 1 0 1 0
d 1 1 1 0

a points to itself, b, and c (directional arrows)
b points to c
c points to a and itself
d points to a, b, and c