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[dragnar]

Bah. I love math, but proofs are EVIL.

Ex: prove that 3x+1 is even if and only if x is odd.

It's ridiculously easy to see that it's true... but proving it is something else entirely.

Spoiler: I'm bored (click to show/hide)

Suppose x is odd and thus can be written x=2n+1 for some n in N.  Then 3(2n+1)+1 = 6n+4 = 2(3n+2) and is even.

Lemma: the product of two odd numbers 2n+1, 2m+1 (n, m in N) is odd.
(2n+1)(2m+1) = 4mn +2(m+n) +1 = 2(2mn + m + n) +1, 2mn + m + n in N because N is closed under addition and multiplication.

To find a contradiction, suppose x is odd and 3x+1 =2m+1, m in N.  Then 3x = 2m, which contradicts our assumption given the lemma.

Helpful Vector is helpful. Thanks... now to figure out the rest of this course.

[Armok]

Helpful Vector is also awesome.

This place REALLY needs a math megathread...

[MetalSlimeHunt]

If we made a math megathread, all of us mathmatically deceaced individuals would constantly be bugging Vector for help. Not the best idea.

[inteuniso]

I've been told that if I ever play football again it will shorten the time I will get extremely painful knee arthritis.

I never even got to experience a full varsity season.  .

[dragnar]

If we made a math megathread, all of us mathmatically deceaced individuals would constantly be bugging Vector for help. Not the best idea.

Hey, Vector isn't the only math person around. She's just several years ahead of the rest of us.

[ToonyMan]

If we made a math megathread, all of us mathmatically deceaced individuals would constantly be bugging Vector for help. Not the best idea.

Yeah, just use the sad thread for it!

[MetalSlimeHunt]

If we made a math megathread, all of us mathmatically deceaced individuals would constantly be bugging Vector for help. Not the best idea.

Hey, Vector isn't the only math person around. She's just several years ahead of the rest of us.

And thus, she is the one we will all think to go to first. Anyway, do we all really want to constantly be helping each other with homework, math or otherwise?

[Leafsnail]

That doesn't actually look like a very good measure of quality of education.  It seems that it's 2 thirds based on adult literacy and 1 third on gross enrollment rates at primary/secondary/tertiary level.

Let's imagine a country that has primary, secondary at teriary schools.  They force everyone to go to these schools on pain of death.  In them, you do nothing except learn how to read and write adequately, then sit around being bored.

This country would have a perfect score on the "Education index".

I mean, don't get me wrong, it's good for measuring accessibility of education in poorer countries, but actual quality?

[Vector]

If we made a math megathread, all of us mathmatically deceaced individuals would constantly be bugging Vector for help. Not the best idea.

Hey, Vector isn't the only math person around. She's just several years ahead of the rest of us.

Eh, I'm halfway through my sophomore year.  I just study a lot.

I don't mind helping people with math, anyhow, as long as they try pretty hard first... I just sort of automatically try to solve math problems when I see them written down >_>;  In reality, I'd hope that a megathread would teach you to help each other.

[MaximumZero]

All this stuff makes my head want to explode. I'm the kind of person who only does math out of necessity.

[Leafsnail]

Oh yeah, the gripe.

What the heck is up with the so called "British" way of writing down decimal points and multiplication symbols?

I mean, apparently, in British notation (which we use at school) 6.7 means "6x7" (with a decimal you need the dot further up... damnit, I can't even find it on a computer).  My new school uses this form of notation.

Now, this seems ridiculous.  For one thing, neither my primary nor secondary school did it.  Nor does any TV programme or book I've read about maths.  Nor does the very calculator the school gets us to buy... indeed, I've never even heard about it until the past two weeks.

So uh... I guess I'd advocate us switching to the American system.  Rant over.

[Vector]

Now, this seems ridiculous.  For one thing, neither my primary nor secondary school did it.  Nor does any TV programme or book I've read about maths.  Nor does the very calculator the school gets us to buy... indeed, I've never even heard about it until the past two weeks.

Because x is one of the most commonly-used variables, and it is very hard to tell 6 (times) 7 from 6x7 = 42x.

America uses dots, too, though I personally tend to use nested parens more than anything else--so 6(7) instead of 6x7 or otherwise.

[ToonyMan]

() work the best yeah.

[Vector]

() work the best yeah.

(brofist)

[Solifuge]

My Stepdad dropped by today, and it was rather nice. He brought some apples he and my Mom had picked, we chatted for a bit, and we took care of some car issues. He also got to meet the kitten, and for a man who long professed his hatred of cats when we were growing up, him saying she was cool was a pleasant surprise. I think I impressed him by the fact that I was studying for my exam, and with some of the things we're doing in Lab. It was rather nice.

Shit, wrong thread. I've got a big honking exam, and a Lab Practical for which I need to know every Animal Phylum like the back of my hand! Doom and Gloom!

If we made a math megathread, all of us mathmatically deceaced individuals would constantly be bugging Vector for help. Not the best idea.

Yeah, just use the sad thread for it!

Zing!