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-   -   Maths: why does 987654321 / 123456789 = 8.000000073 (http://archives1.twoplustwo.com/showthread.php?t=549199)

Dan. 11-19-2007 05:10 AM

Re: NUMBER OF THE BEAST
 
[ QUOTE ]
I have worse news, sir. Try adding the numbers in ROULETTE.

1+2+3+4+...+35+36

Scary.

[/ QUOTE ]

*GASP!*

jessica1994 11-19-2007 06:10 AM

Re: NUMBER OF THE BEAST
 
987654321/123456789 = 8.0000000729000006633900060368490...

which is very nearly 8, except for the isolated 729, 66339, 6036849 ... Now, 729 = 9^3. This isn't a coincidence, as we will see.


Explanation:
Using our prime factor finder program or built-in function, we find that:


729 = 9^3 = 9^3 * 91^0
66339 = 9^3 * 91 = 9^3 * 91^1
6036849 = 9^3 * 91^2 = 9^3 * 91^2

so we can conjecture that:


987654321/123456789 = 8 + 9^3*1E-10*SUM[N=0,N=INFINITE,(91*1E-10)^N]

where the sum goes from N=0 to N=infinite. This can be proved very easily using the well-known summation formula for geometric progressions, as this happens to be one.

john kane 11-22-2007 05:42 AM

Re: NUMBER OF THE BEAST
 
thanks for all the replies and apologies for not replying sooner. the link above has certainly helped me see there is an actual pattern, rather than it being an eerie one-off.

thanks and gl.

Duke 11-22-2007 01:17 PM

Re: Maths: why does 987654321 / 123456789 = 8.000000073
 
[ QUOTE ]
I'd rather someone tell my why cubes add up to squares. Using geomety, not algebra.

[/ QUOTE ]

I'm not convinced that they do.

pzhon 11-22-2007 05:15 PM

Re: Maths: why does 987654321 / 123456789 = 8.000000073
 
[ QUOTE ]
I'd rather someone tell my why cubes add up to squares. Using geomety, not algebra.

[/ QUOTE ]
(1+2+...+n)^2 = 1^3 + 2^3 + .. + n^3.

Proof without Words: Sum of Cubes
Alan L. Fry
Mathematics Magazine, Vol. 58, No. 1 (Jan., 1985), p. 11

I don't have that in front of me, but typically these proofs are inductive. You find some way to illustrate why n^3 = (1+2+...+n)^2-(1+2+...+(n-1))^2. If you fit the smaller square inside the larger, the remainder is an L shape, the intersection of two strips that are n x (1+2+..+n), or a strip that is n x (1+2+...+n) plus a strip that is n x (1+2+...+(n-1)). Break the strips into subrectangles indicated by the sum and pair n x k and n x (n-k), forming n pairs (pair n x n with n x 0) fitting into nxn squares.

MelchyBeau 11-22-2007 05:19 PM

Re: Maths: why does 987654321 / 123456789 = 8.000000073
 
[ QUOTE ]
[ QUOTE ]
I'd rather someone tell my why cubes add up to squares. Using geomety, not algebra.

[/ QUOTE ]

I'm not convinced that they do.

[/ QUOTE ]

he is talking about sum(i^3,i=1,k)=(sum(i,i=1,k))^2

CORed 11-25-2007 02:32 PM

Re: Maths: why does 987654321 / 123456789 = 8.000000073
 
[ QUOTE ]
Uhm.. Because 123456789 * 8 is almost equal to 987654321? Not trying to sound smug but that's all there is to it I think [img]/images/graemlins/smile.gif[/img]

[/ QUOTE ]

123456789 * 8 = 987654312, to be exact.

GoodCallYouWin 11-28-2007 02:27 AM

Re: Maths: why does 987654321 / 123456789 = 8.000000073
 
Someone is clearly trying to send us messages through the fabric of spacetime itself.


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