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The most amazing mathmatical statement ever.

croxiscroxis I am the walrus
e^(pi*i)=-1


......

CAN SOMEONE EXPLAIN THIS TO ME?!?!?!?!?!

Comments

  • Lord RefaLord Refa Creepy, but in a good way
    0wn3d
  • BekennBekenn Sinclair's Duck
    Yeah, that one floored me when I first saw it, too. After that I learned two or three different ways of proving it... and then promptly forgot them. It's a pretty important equation for digital signal processing.
  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    Please, never mention that equation again. It brings back such horrible memories...
  • ShadowDancerShadowDancer When I say, "Why aye, gadgie," in my heart I say, "Och aye, laddie." London, UK
    what? this equation e^(pi*i)=-1 ? but it just looks so damned cute!:D
  • fuck math.
  • RhettRhett (Not even a monkey)
    Analytic calculus cant help me with that (at least not yet)
  • JackNJackN <font color=#99FF99>Lightwave Alien</font>
    I assume the (pi*i) portion has something to do with Sine waves and/or frequency?

    Are "e" and "i" Voltage and Current or ?

    The negative 1 value in a digital environment ?

    Hmmmmm... almost looks like it's dealing with an area value in a plane.

    eh... What do I know anyway...


    :rolleyes:
  • Random ChaosRandom Chaos Actually Carefully-selected Order in disguise
    eix = cos (x) + i sin (x)
    (this can be shown using the series expansion of e, cos, and sin)

    So,

    eiπ = cos (π) + i sin (π)
             = -1 + i * 0
             = -1

    --------------
    Taylor series expansions:

    ex = ∑(n=0..∞) xn/n! = 1 + x/1 + x2/2 + x3/6 + x4/24 + x5/120 + ...

    Which means

    eix = ∑(n=0..∞) (xi)n/n! = 1 + i*x/1 - x2/2 - i*x3/6 + x4/24 + i*x5/120 - ...

    Which is the same as [b]cos (x) + i sin (x)[/b], where cos and sin are as follows:

    cos (x) = ∑(n=0..∞) (-1)n z2n/[(2n)!] = 1 - x2/2 + x4/24 - ...
    sin (x) = ∑(n=0..∞) (-1)n z2n+1/[(2n+1)!] = x - x3/6 + x5/120 - ...


    Note also:
    cos (x) = 1/2 * [eix + e-ix]
    sin (x) = 1/(2i) * [eix - e-ix]
  • RhettRhett (Not even a monkey)
    Yea I guess it comes down to what the variables stand for. Is that the imaginary number i or a variable i?
  • Random ChaosRandom Chaos Actually Carefully-selected Order in disguise
    Imaginary number (i or j, take your pick based on whether you are a mathematician/scientist or engineer)

    Note: Hope everyone can read the symbols in the above - I don't know if all browsers handle the full W3C spec on HTML codes. I have used ∞, π, and ∑ to simplify it, but some browsers might balk :)
  • JackNJackN <font color=#99FF99>Lightwave Alien</font>
    I thought it was "Pi * i " in parenthesis?
  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    Only because croxis was writing it without superscript. It's written the way RC wrote it, because i isn't a variable, it's a notation for imaginary numbers. Personally, I'm a j person but that's because I'm an engineer. If we use i for imaginary numbers it gets mixed up with our currents. :D
  • PhiPhi <font color=#FF0000>C</font><font color=#FF9900>o</font><font color=#FFFF00>l</font><font color=#00F
    One of my favourite equations :) Thanks RC for doing it justice ;) Though I must say...Taylor series...*shudder* eeeeevil....

    Coincidentally, we derived E=mc^2 in Physics today. T'was fun.

    But calculus doesn't *really* get fun until you're calculating the curl of the gradient of a function over the space curve defined by the intersection of an elipsoid and a hyperbolic paraboloid... :eek:

  • TyvarTyvar Next best thing to a St. Bernard
    :noidea:


    pretty much sums it up for me.

    Reading Kant is so much easier :P
  • Random ChaosRandom Chaos Actually Carefully-selected Order in disguise
    [QUOTE][i]Originally posted by Phi [/i]
    [B]One of my favourite equations :) Thanks RC for doing it justice ;) Though I must say...Taylor series...*shudder* eeeeevil....

    Coincidentally, we derived E=mc^2 in Physics today. T'was fun.
    [/b][/quote]

    Actually the proper reletivistic equation is E=γmc2

    At rest, γ=1 thus the reason why E=mc2 gained prominence since it indicated the rest energy of any mass.

    [quote][b]
    But calculus doesn't *really* get fun until you're calculating the curl of the gradient of a function over the space curve defined by the intersection of an elipsoid and a hyperbolic paraboloid... :eek:

    -Φ [/B][/QUOTE]

    Fun. Gradient isn't hard. What I hated was calculating line, surface, and volume integrals over strangely defined (but common) objects.
  • Random ChaosRandom Chaos Actually Carefully-selected Order in disguise
    [QUOTE][i]Originally posted by JackN [/i]
    [B]I thought it was "Pi * i " in parenthesis? [/B][/QUOTE]

    Can you see the difference between:

    eiπ
    eiπ

    If not, your browser is obsolete and doesn't handle the superscript HTML command.
  • PhiPhi <font color=#FF0000>C</font><font color=#FF9900>o</font><font color=#FFFF00>l</font><font color=#00F
    [QUOTE]Fun. Gradient isn't hard. What I hated was calculating line, surface, and volume integrals over strangely defined (but common) objects.[/QUOTE]
    Indeed...that would be the exam in two weeks. Whee :rolleyes:

  • Random ChaosRandom Chaos Actually Carefully-selected Order in disguise
    heh...what course?

    I had to do that stuff in just about every other physics course I took. Fun. :rolleyes:
  • PhiPhi <font color=#FF0000>C</font><font color=#FF9900>o</font><font color=#FFFF00>l</font><font color=#00F
    Second year calculus.

    In physics we're just doing Newtonian mechanics (linear and angular), plus a smattering of special relativity....I think our teacher is afraid of scaring people (most of whom aren't in math) so he tends to avoid anything more complicated than integraton.

  • BigglesBiggles <font color=#AAFFAA>The Man Without a Face</font>
    [QUOTE][i]Originally posted by Phi [/i]
    [B]But calculus doesn't *really* get fun until you're calculating the curl of the gradient of a function over the space curve defined by the intersection of an elipsoid and a hyperbolic paraboloid... :eek:[/B][/QUOTE]

    AHH! AHHHHH! FLASHBACKS! MAKE THE HURTING STOP!
  • [QUOTE][i]Originally posted by Tyvar [/i]
    [B]Reading Kant is so much easier :P [/B][/QUOTE]:D
    Stupid engineers/mathematicians and their "facts." I like fields of study where I can defend and answer with the proper support.
  • BekennBekenn Sinclair's Duck
    Well, that's what I like about the hard sciences: you can easily defend and support any correct answer.
  • Erm, defend [i]any[/i] answer.
  • JackNJackN <font color=#99FF99>Lightwave Alien</font>
    [QUOTE][i]Originally posted by Random Chaos [/i]
    [B]Can you see the difference between:

    eiπ
    eiπ

    If not, your browser is obsolete and doesn't handle the superscript HTML command. [/B][/QUOTE]

    Yes, I can see the difference. It was just my ignorance that assmued it was the Value of Pi * i

    :rolleyes:
  • JackNJackN <font color=#99FF99>Lightwave Alien</font>
    [QUOTE][i]Originally posted by Phi [/i]
    [B]But calculus doesn't *really* get fun until you're calculating the curl of the gradient of a function over the space curve defined by the intersection of an elipsoid and a hyperbolic paraboloid... :eek: [/B][/QUOTE]

    For that you would need Spock's Brain...

    :p
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