Math Is Fun Forum

  Discussion about math, puzzles, games and fun.   Useful symbols: ÷ × ½ √ ∞ ≠ ≤ ≥ ≈ ⇒ ± ∈ Δ θ ∴ ∑ ∫ • π ƒ -¹ ² ³ °

You are not logged in.

#101 Re: Maths Is Fun - Suggestions and Comments » a bit of an issue » 2009-08-01 02:25:04

MathsIsFun wrote:

Pictures: use any drawing program (from paint to photoshop. I like Inkscape myself) to create the image on your computer, and then upload it into your post.

Have a try and ask questions if you get stuck.

The thing is  Soroban didn't use drawing software, they did it with the Maths cod, I was asking how to do that?

Thank you

#102 Re: Puzzles and Games » Making a necklace » 2009-08-01 02:21:09

The answer is $8 Just break up one chain into it's 4 links and put them between the remaining four and then close them.

Look at my thread chain puzzles for some harder ones:D

#103 Re: Maths Is Fun - Suggestions and Comments » a bit of an issue » 2009-08-01 00:42:33

MathsIsFun wrote:

Oh, I am sorry, wintersolstice. Your post was thought provoking, no doubt.

For me soroban's post had the instant appeal of seeing the chains ... I just wanted to link them up! (BTW, that puzzle is not solved yet.)

Why don't you add a post on your topic, something like, "OK, try solving this one: ... "

Well maybe if I could do pictures of chains (I don't don't how!) the 1-100 chain puzzle would be hard to draw without the ellipses.

You see no-one asked what my puzzles were about so if someone could tell me how to do pictures, I could make some other chain puzzles. There's a trick to ones with chains of different lenghths (an idea of my own:D)

thanks

#104 Maths Is Fun - Suggestions and Comments » a bit of an issue » 2009-07-31 06:15:55

wintersolstice
Replies: 7

I couldn't go private with this issue (because I don't have Private messaging yet)

Basically I posted a puzzle in this thread http://www.mathisfunforum.com/viewtopic.php?id=12270

No-one answered (fair enough!)

but then someone posts "exactly" the same puzzle as me but states it differently in this thread http://www.mathisfunforum.com/viewtopic.php?id=12454

And people are on it like a shot even though it's the same puzzle!

Now in my thread I had come up with the idea to extend such puzzles to include harder ones.
Since I had "invented" this idea (the extension not the original puzzle) I was annoyed (and hurt) that people ignored it but didn't when someone posted the original puzzle.

I posted in the second thread to say that I had already posted this puzzle and no-one had answered, and I was ignored (again!)

I don't want to cause trouble nor am I trying to make a big deal, I just feel hurt.

#105 Re: Puzzles and Games » Making a necklace » 2009-07-30 08:15:38

Funny how when I posted this puzzle(and it was the "exact" same puzzle!)
(in the "chain puzzles" thread) with some harder ones aswell, no one answered. So what did I do wrong?

#106 Re: Help Me ! » Help me complete my math assignment » 2009-07-21 21:35:48

I don't have the full solution here, but I think I've deduced what the polynomomial is (I'm just not very good at factorising!)

#107 Re: Puzzles and Games » positive integers » 2009-06-23 00:21:46

In fact the method I've got just re-writes the puzzle so it's pointless.

#108 Re: Puzzles and Games » positive integers » 2009-06-23 00:10:40

mathsyperson wrote:

Without getting into that debate though, (0,0) is not a solution because tony's interested in positives.

Ok I didn't read the puzzle properly and sorry for going on about the "0^0" debate

I think it's safe to assume that (1,1) is the only solution for A=B I think I have something that could help see if there's solutions for A≠B. (but it's complicated)

Should I explain my idea?:D

#109 Re: Puzzles and Games » positive integers » 2009-06-22 23:34:58

mathsyperson wrote:

0^0 is a tricky creature. Some people insist that it's equal to 1, some think it's 0 and others say it doesn't have a value at all.

Without getting into that debate though, (0,0) is not a solution because tony's interested in positives.

saying that 0^0 = 1 is actually incorrect (I read it somewhere!)

plus there's (-1,-1)

also there's something very completed that I discovered that could uncover another solution

if 0^0 = 1 then 0/0 = 1

this means that
(0/0)*5 = (0/0) would simplify to 5=1 (this is a paradox)

#110 Re: Puzzles and Games » positive integers » 2009-06-22 22:38:28

I hope I'm not breaking any rules here (two many consecutive posts!) I just spotted a mistake in my proof that makes me think there are other solutions!

#111 Re: Puzzles and Games » positive integers » 2009-06-22 21:09:12

bobbym wrote:

You are right and I think we can prove it like this.

I think I can prove that A must equal B by extending your proof (your prove was just incomplete)  and I know of another solution (0,0)!

which means that:

#112 Re: Puzzles and Games » positive integers » 2009-06-22 20:36:18

bobbym wrote:

Divide both sides by log(A)


Now since
is an integer and
could never be an integer.

We have a contradiction. So there are no other solutions besides (1,1).

If B is a power of A then it 

can be an integer so that's not a contradiction.

#113 This is Cool » 4D and beyond » 2009-06-21 22:15:35

wintersolstice
Replies: 0

In my investigations about 4 and higher dimensional shapes, I've discovered how to make an "antiprism"  in 4D+ and my discovery is that the only uniform antiprism in 4D+ is an the "Orthorplex"

And I've discovered that a pyrimid is self-dual if and only if it's base is self dual.

#114 Maths Is Fun - Suggestions and Comments » "regular polyhedra" » 2009-06-20 01:14:22

wintersolstice
Replies: 1

In the "Mathsisfun" page, it says there are only 5 regular polyhedra ("the Platonic solids (or regular polyhedra)") 

There are actually nine regular polyhedra, the 5 Platonic solids and the 4 Kepler-Poinsot solids. A Platonic solid is a regular "convex" polyhedron. The other 4 are star polyhedra.

#115 Puzzles and Games » Chain Puzzles » 2009-06-16 21:44:44

wintersolstice
Replies: 10

There's a type of puzzle that I call a "chain puzzle". Basically you have a given number of chains and your given how many links they have. Your job is work out, "What is the minimum number of links that need to be broken and rejoined to make a continuous loop?"  The notation I'd use for stating a puzzle is to list the number of links in each chain.

So 3,4,5 would mean there are 3 chains, one has 3 links, one has 4 and the other has 5.

I would say there are three levels of difficulty:

"all the same" = easy
"From one to a given number consecutive" = medium
"totally random" = hard

easy: 4,4,4,4,4

medium: 1,2,3,4...99,100 (all the numbers from 1-100)

Hard: 4,5,6,7,12,16,21,41,61,63,71,72,71,72,73,74,80,81,83,85,90,100,101,109,121,131,132,   133,135,136,138,140,144,145,150,161,162 (you can take your time with this one)

Tell me what you think:D

#116 Re: Puzzles and Games » Chess Puzzles » 2009-06-16 01:27:19

#34. If a king is on the same line as a piece that can threaten it in that direction, but has one of it's own pieces protecting it, that piece (the protecting piece) is only allowed to move to squares on that line, if the enemy king is in a place where it is threatened by the protecting piece, the protecting piece can't capture the king because that would put it's own king in check, so is the the king (enemy king) in check?

#117 Re: Puzzles and Games » Does anyone know the answers to these questions PLS! » 2009-06-15 01:42:03

quiz_me wrote:

1. What kind of tree does a cat hide under during a rainstorm?

2. What can stand upright and lie on its face at the same time?

#118 Re: Help Me ! » Polychora » 2009-06-09 21:12:56

integer wrote:

A google search will give a lot of information and some of the facet/edge/lines count.

integer wrote:

A google search will give a lot of information and some of the facet/edge/lines count.

I already know what the count is (edges faces etc) I want to know where they come from. I can prove that it is:

X is 120. why?

#119 This is Cool » seven and thirteen » 2009-06-07 23:37:40

wintersolstice
Replies: 11

7 and 13 are the first two happy primes and 91 (7×13) is also a happy number. this means that 19 is happy, this is the 3rd happy prime!

#120 Re: Introductions » Hello all » 2009-06-07 22:35:12

MathsIsFun wrote:

Welcome! Were you born on the Winter Solstice?

No!:lol: I just like the word(s)

#121 Help Me ! » Polychora » 2009-06-07 22:31:31

wintersolstice
Replies: 3

I read some info about polychora (4D Polytopes) and have read that the 4D analog to a icosahedron has 600 cells (which are tetrahedra) but when I tried to prove it I came up which several values (none of which were 600!) The other principle is that it has 5 faces at each edge.

Can anyone explain why it's 600?

and the self dual regular polychoron which uses octohedral cells has 24 cells. Why?

I also wouldn't mind knowing the pronunctiation of "polychoron" I think it's "poly-kor-on" but I'm not sure.

#122 Introductions » Hello all » 2009-06-06 02:06:20

wintersolstice
Replies: 6

Hello all.  I've been a Maths fanatic for as long as I can remember, and have always wanted to find someone who shares my passion for it. The only branch of maths I don't like is "statistics"
I also do maths problems as a hobby.

Board footer

Powered by FluxBB