Quantum Pontiff
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Ln 2

June 3, 2007 on 6:38 pm | In General |

Now that’s a CAPTCHA. Reminds me, for some reason, of John Conway not allowing himself to log in unless he could correctly identify the day of the week of a given random date.

8 Comments »

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  1. It is tooooooooooo easy: ln(2)

    Comment by Eliatron — 6/4/2007 #

  2. sin 1/0 is something between [-1,1], and arctg 0=0. Any value between -1 and 1, 0 times, is 0. Square root of 0 is 0…

    Comment by Daniel — 6/4/2007 #

  3. But nice way to avooid bots…

    Comment by Daniel — 6/4/2007 #

  4. ARCTG 1/0 = INFINITO
    SEN 0 = 0
    0 X INFINITO = 0
    SOLUTION = LN2 = 0.69314718

    Comment by GEORGE — 6/4/2007 #

  5. 0 x INFINITO != 0, be carefull ;)

    Daniel’s solution is the correct one

    Comment by Guiller — 6/4/2007 #

  6. the solution is ln2, because, if the limit exists, it will be the sum of ln2 (a constant) and the lim(sqrt(arctg x . sin(1/x))), and this one is the sqrt(lim(arctg x. sin(1/x))), and this limit is 0, because, although lim(sin(1/x)) does not exist when x->0, is between -1 and 1, so this function, multiplied by another whith limit = 0 when x->0, as arctg x, has limit 0. So, finally, ln2+0=ln2.

    Comment by tanausĂș — 6/4/2007 #

  7. I hate to point it out to everyone commenting, but I think the title of this post kind of gave the game away.

    Comment by Joe Fitzsimons — 6/4/2007 #

  8. i think that is not about the solution, it’s about how to get the solution, so in my opinion, the explanations are necessaries.

    Comment by tanausĂș — 6/5/2007 #

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