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#376 Re: Help Me ! » Permutation » 2006-06-10 06:10:16

Another challenge...
Find the largest value of k so that 10^k divides:

#377 Re: Help Me ! » Permutation » 2006-06-10 06:08:50

Another answer...
Because the number actually is:
4711930799906184953162487834760260422020574773409675520188634839616415335845034221205
2892567055446819724391040977771579918043802842183150387194449439904925790307206359905
38452312528339864352999310398481791730017201031090

As you see, it ends with 1 null.
smile wink smile

#378 Re: Help Me ! » Master Sum » 2006-06-10 03:02:39

Good question.
I want YOU to sweat a little.

#381 Re: Help Me ! » logic » 2006-06-10 02:56:32

Oh, yes...
"What's the truth value of..."
tongue

#382 Re: Help Me ! » the biggest circumference !? » 2006-06-10 02:54:42

A note: there may exist a figure with arbitary circumfence and constant area.
For the original question:
The figure with the biggest circumfence is the most "angular"(the most different from a circle) figure.

#383 Re: Help Me ! » Pure problem » 2006-06-10 02:49:50

Only game???
Where's the maths?

#384 Re: Help Me ! » logic » 2006-06-09 02:42:20

There might be a mistake. Why didn't you use Ex?

#387 Re: Help Me ! » ... equation ... » 2006-06-03 21:28:46

Another "solutions":



ect.
I will accept solutions like 0 and infinity, if they are fully defined (e.a. 0*infty==?).

Edit: I have just thought something:
We can say 3/0=4/0 in a way-3/0 and 4/0 are both indeterminate (if we assume that 2 indeterminates are equal).

#388 Re: Help Me ! » Problem » 2006-06-03 21:20:35

Here's the code (Mathematica, rewritten, but really messy and hard-to-understand):

K[n1_, n2_] := Union[{n1 + n2, n1 - n2, n1*n2, n1/n2}];
KK[list_, num_] := Union[Flatten[Table[K[list[[i]], num], {i, 
      1, Length[list]}]]];
KKK[list1_,
     list2_] := 
      Union[Flatten[Table[KK[list1, list2[[i]]], {i, 1, Length[list2]}]]];
d[a_, b_, c_, d_, f_] := {
    (*abcdfff*)
    f[{a}, f[{b}, f[{c}, {d}]]],
    (*abcfdff*)
    f[{a}, f[f[{b}, {c}], {d}]],
    (*abcffdf*)
    f[f[{a}, f[{b}, {c}]], {d}],
    (*abfcdff*)
    f[f[{a}, {b}], f[{c}, {d}]],
    (*abfcfdf*)
    f[f[f[{a}, {b}], {c}], {d}]
    }
d[l_, f_] := d[l[[1]], l[[2]], l[[3]], l[[4]], f];
dd[l_, f_] := dd[l[[1]], l[[2]], l[[3]], l[[4]], f];
dd[a_, b_, c_, d_, f_] :=
  (
    Print["abcdfff:", f[{a}, f[{b}, f[{c}, {d}]]]];
    Print["abcfdff:", f[{a}, f[f[{b}, {c}], {d}]]];
    Print["abcffdf:", f[f[{a}, f[{b}, {c}]], {d}]];
    Print["abfcdff:", f[f[{a}, {b}], f[{c}, {d}]]];
    Print["abfcfdf:", f[f[f[{a}, {b}], {c}], {d}]];
    )
p = Permutations[{3, 3, 8, 8}];
res = Table[Union[Flatten[d[p[[i]], KKK]]], {i, 1, Length[p]}];
Union[Flatten[res]]

Could explain and rewrite it later.

#389 Re: Help Me ! » Problem » 2006-06-03 21:10:31

This program was personal challenge.
Here's list of all numbers, which can be expressed using 8,8,3,3:

#390 Re: Help Me ! » Problem » 2006-06-03 21:08:17

My program is ready. And guess what-there aren't another solutions except:
8/(3-(8/3))=24!!!

#392 Re: Help Me ! » Problem » 2006-06-03 19:27:08

Interesting... Can't you make some program, which gives all possible solutions?

#394 Re: Help Me ! » infinitesimal values questioned. » 2006-06-03 04:07:09

I have to aknowledge i can't really understand the infinitesimal (although I use it).
Here's my question-is it well-defined - does it REALLY exist?
How can a number be greater than infinity?

#395 Re: Help Me ! » ... equation ... » 2006-06-03 03:59:42

OK. x is not "exactly" null. But what's happening if x is infinitesimal?

#397 Re: Help Me ! » ... equation ... » 2006-06-02 20:48:37

Thank you. I tryed with \text{...}, but it gave an error.

#398 Re: Help Me ! » infinitesimal values questioned. » 2006-06-02 20:46:18

Can't we create our own "objects" as infinitesimals?
Let p be 1 in multiplication and 2 in addition...
What happens???:
for a-real:
pa=a;
p+a=a+2;
p(p+a)=p^2+pa=a+2, so p^2 must be 2 smile (but only in addition smile)
(p+a)/p= (a+2)/p=a/p+2/p=a/p+2;
(p+a)/p=p/p+a/p, so p/p=2/p=2.
Others:
(p* means p is used in mult.
p+ means p is used in addit.)
2p-p=2(p*)-(p+)=2-2=0. it is different from:
2p-1p=2(p*)-1(p*)= (2-1)(p*)= (p*)=1.
1p=1=1(p*)=1.1=1.
1(p+0)=1((p+)+0)=1(2+0)=2.
The basic laws won't be true.

#399 Re: Help Me ! » infinitesimal values questioned. » 2006-06-02 20:33:09

Interesting...
So an infinitesimal is a "number", which behaves as a real number in multiplication, and, as 0 in addition... smile

#400 Re: Help Me ! » ... equation ... » 2006-06-02 20:20:18

Consider a function: {x} - the real part of x. ({2.5}=0.5, {5/3}=1/3, {sqrt(2)}=sqrt(2)-1}).
Let see what's the limit as x goes to 2.
Here we have 2 different limits: left-limit and right-limit:



See? You can't conclude what is f(x) using only limits.
(and there are more interesting examples: the function

)
smile
::Edited. Changed some latex text.

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