

The math behind a neat calculator trick - signa11
http://divisbyzero.com/2010/02/17/the-math-behind-a-neat-calculator-trick/

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te_platt
If you want to work it out yourself first here is the trick. Set calculator to
degree mode, enter a bunch of fives (5555 or 55555555), take the reciprocal,
take the sin, note similarity to pi. Very fun article.

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dutchflyboy
While the trick is quite nice, I personally just press the "PI" button...

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gokhan
Calc's are funny.

Try 12345679 * 9x (where x < 10)

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csomar
So what will happen? (tried on all my calc's and they gave the same result as
<http://www.google.com/search?q=12345679+*+92>, which I think it's correct).

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CrazedGeek
Try 123456789 * 9 * 2.

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csomar
So what result should I be expecting? I'm getting a correct result on my Sharp
EL-506W

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studer
12345679 * 9 * x where x is a single digit gives you nine copies of x.

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est
Here is how to get e using a calculator:

sinh(1) + cosh(1)

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hackermom
pi / 180 = 0.01745 (a value commonly used for degree<->radian conversion). 1 /
180 = 0.0055555. That's the connection between the "magic" constants used in
this trick.

It brings an older, simpler, not nearly as interesting calculator "trick" to
mind: 11111111 * 11111111.

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imurray
_It brings an older, simpler, not nearly as interesting calculator "trick" to
mind:_ 11111111 * 11111111.

    
    
      gnuplot> pr 11111111 * 11111111
      -2047269199
    

:-). For the intended result, people can put a '.' after one of the numbers to
make it a double, or use a better calculator like bc or Python.

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cliveholloway
Much too highbrow for me.

39103 * 136

Then turn your calculator upside down and read the result.

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hugh3
Sure, but can anyone explain 5318008?

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jpeterson
Wow, I can't believe this made it to the top of Hacker News. Tranformation to
Reddit complete!

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Shamiq
Oh no.

