PDA

View Full Version : Any math nerds know what a "U" (subset) is?

Twilight
05-03-2001, 01:44 AM
Ok, so i missed a few math classes.. i've been sick for the last two weeks. I just got into a section on sets, counting, permutations, combinations, partitions and other crap... and i don't know what this little U thing is, other than it's called a subset. It's facing different directions in different problems... what do I do with it? Help!

GilbertsGrape
05-03-2001, 02:18 AM
found this on M-w.com maybe that will help some ....

Main Entry: non-U
Pronunciation: 'nän-'yü
Date: 1954
: not characteristic of the upper classes

maybe try
http://www.useekufind.com/learningquest/tmath.htm

http://www.math.ufl.edu/math/math-web/mathmost.html

http://www.math.ufl.edu/math/math-web.html

Twilight
05-03-2001, 02:24 AM
Hmm well, so far I've figured out that when the U is laying this direction "(" it means that for example 2,5,9 is a subset of 1,2,4,5,7,9. That's cuz 2,5,9 are all contained within 1,2,4,5,7,9. But I don't know what it means when the U is facing other directions.

despayre
05-03-2001, 03:17 AM
when it looks like this: U

it means the union of two sets. for example, {1,3,5,7}U{2,4,6,8} means "combine the sets into one big set". so the result would be {1,2,3,4,5,6,7,8}

when it looks like an upside-down U (no ASCII value for it) it means the intersection of two sets. for example, {1,3,6,8,11,14} "U" {2,8,14,19,49} means "take only the members that occur in both sets". so the result would be {8,14}

revil
05-03-2001, 04:05 AM
Ah, that's simple stuff.

zenbooty
05-03-2001, 01:07 PM
Seriously. Call me when you have a real question, like Green's or Stoke's theorems or something. :)

eSDee
05-03-2001, 02:37 PM
How about Laplanche(sp?) transforms. Oh man those kicked me in the jimmy!

zenbooty
05-03-2001, 02:43 PM
Originally posted by EsDeeLoco
How about Laplanche(sp?) transforms. Oh man those kicked me in the jimmy!

Ooh yeah. Both LaPlace and Fourier transforms sucked big time. I was a math double major, but diff eq. was definitely my weak point. Abstract and linear Algebras and stats were more my thing. Oh, and combinatorics was just plain fun.

ProMinx
05-03-2001, 08:19 PM
Green's and Stoke's aren't too bad...and LaPlacians never get bad until you actually have to apply them in physics, but we all have our opinions. Oddly enough...I hate my math classes.
ProMinx

theorangeone
05-03-2001, 08:32 PM
shudder shudder
diff eq is the only class i came even close to failing. i actually liked math up until that point.

coleslaw
05-04-2001, 02:28 AM
Laplace transforms are cake. They make differential equations simple to solve. Of course, when you throw in Fourier transforms and z-transforms, it can get a little confusing, but us electrical engineers don't like classical differential equations.

coleslaw
05-04-2001, 02:30 AM
Oh yeah, and then there is the Schroedinger equation and its derivatives. Don't get me started... don't even get me started!!

TheLoneGunman
05-04-2001, 03:20 AM
Eigenvalues...

manual T-tests...

programming SPSS

Do they still do any of these in school?

All completely useless in the world of Excel.

coleslaw
05-05-2001, 03:55 AM
oh yeah, eigenvalues are still floating around. drats!