Strange, stupid or cool maths formulae.

[Dreamlax]

Hi all. For school we have to make interesting web sites to put up on the local intranet, and I decided to do mine about strange stupid or cool maths formulae. It probably won't be interesting but I like to look at them anyway. Even if they don't work (ie the one in the 2 = 3 thread) I'd still want it.

[DavidHooper]

Go here and look for a couple. The best I could find is the one with the sqrts, part-way down this page.

Reminds me of a game my brother and I used to play - finding the best at www.securityarms.com.

[MathImagics]

In the cool, I would definitely include this well-known, but always elegant, equation:

        i * pi
      e       +    1   = 0

It encapsulates, in one subtle, but by no means obvious, equality, arguably the 5 most fundamental numbers of all, i.e. unity, zero, pi, e and i.

It's cool also because it combines the imaginary with the transcendental, which is kind of cosmic, or kharmic, or something....

Dr Memory

[bugzpodder]

i invented these two equation (of course, they work, seriously):
i^i^i^i^i=i
i^i^i=-i


btw i think e^(i*pi)+1=0

there shouldn't be a negative. but adding a negative and the equation STILL holds.

of course, there is
i^i=.2078795764


some nice formulas are calculating the area of any convex polygon and find the area of triangle and and quadrilateral from the side lengths.

demoivre's theorem is kool

trig identity sin^2(t)+cos^2(t)=1 is also kool

also go dig up the formula for finding pythagras triples. its really impressive

but most importantly, instead of just adding formulas, try to add a way to develop the formula. that'll make your site the most impressive, if you find the time to do it.

btw to David, now i am convinced that it isn't an amateur site lol

[MathImagics]

I was on my way home from work, thinking "did I put a minus-sign in that formula? Surely not!" - it was a slip of the keyboard!

By the way, it was really eery visiting this forum (not this site) for the first time, only to discover I had already been here before! I know Jim White is not a very rare name but...... ... 2 VB programming, mathematically-inclined JW's on the same forum??? Spooky!

And now I have no choice but to reveal Dr Memory's secret identity... which I just did.....

If I ever change my name by deed poll, I think I'll opt for something a tad less common, like McGannahan Skjellifetti ... oh nuts! Somebody already thought of that one, too!


Dr Memory & Mr White

[bugzpodder]

lol he suggested the same formula! now thats 3 jim white's that i know lol

[MathImagics]

3???????????????????????? Ommagawd!!!!!

[MathImagics]

Hey, bugzpodder! I was at Uni of Waterloo once upon a time.... how's Ontario treating you?

Dr Memory

[bugzpodder]

lol i am interested in going to UoWaterloo when i grad. at least thats what my math teacher mr. white want us to do (lol his son is James White, but James-Jim no difference lol) I heard there is this math+computer science degree (either major in math with computer science or the other way i don't remember) at length thats what i am interested in. I am also interested the Software Enginneering program they are offering. i think it started just last year. i was their just 2 month ago, and like the campus a lot. I think i stayed at Village 3, which is new and really nice.

[MathImagics]

Both those courses sound very worthwhile - UofW has always had a good reputation. I was there quite a while back! I did computer science in Canberra, Australia - I was doing a sub-major in Applied Maths, and my lecturer was a big fan of Combinatorics - back in the early 70's this was quite a new field, and Waterloo was THE place to be - the authors of all the best textbooks in that field were all in residence there - they had a Department of Combinatorics and Optimisation.

My lecturer sent over some of my work (I seemed to take to this subject like a duck to water), and was invited over - I worked as a calculus tutor there (in 74/75) and sat in on some Masters course subjects, but without a grounding in Pure Maths I was out of my element, and later returned to Australia and a career as a Software Engineer..

If you studied there, I doubt that you would ever regret it...

P.S. My son's called James (of course!) - go the Whites!!!!

Dr Memory

[DavidHooper]

btw to David, now i am convinced that it isn't an amateur site lol

I like it because it's very in-depth and actually has some up-to-date maths news, such as this article.

[snakeeyes1000]

i don't know if this is what you want, but I got proof that .999... repeating is equal to 1.

.111... = 1/9

.999... = .111... * 9

(1/9)*(9/1)=1

.999... = 1

[Alphanos]

Hey bugzpodder, I'm thinking of going to Waterloo for university as well! When do you graduate?

[Dreamlax]

This stuff is great, it's exactly what I wanted! Thanks snakeeyes1000, DavidHooper, MathImagics and bugzpodder!

I'm thinking I need not just formulae, but mathematical concepts and debates. Mind you they are flying all around this forum, so I'll pick the ones which have 'suitable' language...