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#651 2011-06-11 02:27:41

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

You mean ignorant and ignorant of it.

I have seen people who are ignorant and adamant.

How could you? They all live here.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#652 2011-06-11 03:24:31

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Yes!

How could you? They all live here.

May not be all of them, they are randomly and non-uniformly distributed, each possessing ignorance in different quantities!

I was trying http://www.mathisfunforum.com/viewtopic.php?id=15630,
how to solve x^(1/x) == 243, numerically?
I did not understand the output of wolframalpha, and newton raphson method doesn't seem to give the right answer.


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#653 2011-06-11 10:54:31

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

You probably solved it symbolically. Few equations really can be solved like that. This one involves the Product Log.

Wolfram has an NSolve and FindRoot command. I believe Sage does to ( Find_root). These work numerically. Here is another way that works in this case:

Enter "x^(1/x)==243"

You will see a solution and a button marked Approximate Form.

Click that and you will get.

.166623 - .364093i you can now get more digits by clicking the More Digits button. You should be able to use Newtons Iteration on that as an initial guess.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#654 2011-06-11 16:58:35

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Hi bobbym,

I think find_root in sage works only for reals.

Anyway, I found a way to output the approximate solutions in wolfram, I took one of the productlog solutions and entered the command :
Table[N(e^(-ProductLog[-5 log(3) - 2 i n pi])),{n,10}]

But still, it's difficult to solve for A, B, C subject to condition A*B*C = 1.
Now I'm beginning to doubt whether it has a solution at all !


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#655 2011-06-11 17:28:35

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

Are those solutions?


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#656 2011-06-11 17:40:33

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Those are solutions for the equation  x^(1/x) = 243

I'm trying to find x,y,z such that x^(1/x) = y^(1/y) = z^(1/z) = 243 and x*y*z = 1
Do you think it's possible to have a solution?


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#657 2011-06-11 18:14:58

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

That is the question that has been posed on this forum. I have stayed out of it because I do not think the OP knows the right answer, or even knows if there is one.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#658 2011-06-11 18:24:31

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Hi bobbym,

Yes, and I don't know whether the OP was serious, after looking at some of his replies!
Anyway, I'm just curious.


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#659 2011-06-11 18:34:24

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

It looks like there are an infinite number of solutions, all of which are imaginary numbers.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#660 2011-06-11 18:40:12

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

I was trying to find atleast one such (x,y,z) pair, still not able to find one.


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#661 2011-06-11 19:04:36

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

I have not found one either. Each time I manipulate your equations and get a solution it never works when plugged in.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#662 2011-06-11 19:47:29

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Same with me.

Manipulating it, I got another condition:

Then I thought it's sufficient to solve xyz=1 and x+y+z=0.
But strangely, the solutions didn't work!


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#663 2011-06-12 00:38:28

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

No solutions that I can find.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#664 2011-06-12 00:48:32

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Hi bobbym,

Ok, no problem.


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#665 2011-06-12 01:15:04

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

Everything I am doing looks fruitless. It could be that there are not any solutions.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#666 2011-06-12 01:34:25

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Hi bobbym,

Yes, that's what I think too.
I think I'll go crazy if I try it any longer!


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#667 2011-06-12 01:59:06

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

I know what you mean!


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#668 2011-06-23 00:38:51

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

New Problem!

A believes he can stump our panel, even though he is on it! But he dislikes B and E so much he can not help himself. He poses this:

Each person is to get an equal amount of gold and an equal number of sacks. The sacks are of three types. Empty, half full and full. There are n of each type. So if n = 2 then there are (empty) (empty) ( half full ) ( half full ) ( full ) ( full ).

One way to split the gold with those 6 sacks is

Person 1) ( full ) ( empty )
Person 2) ( full ) ( empty )
Person 3) ( half full ) ( half full )

They each have the same amount of gold and the same number of sacks. How many ways are there if n = 100. Can you find a general formula for any n?

A says) I have stumped you all! Including myself!
B says) You are losing it A! Calm down and let me work on it.
C says) I got it. 182763548917624567373891872653412 ways
D says) That is incorrect.
E says) That is not even close and where is your general formula?


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#669 2011-06-23 00:50:16

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Hi bobbym,

Can they all get only empty sacks?(No gold to any of them)


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#670 2011-06-23 00:54:33

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi;

No, you want to split the gold equally among the three of them.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#671 2011-06-23 01:03:46

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Okay, I think I misunderstood the question.

For n=2, there are 3 units of gold.
For n=3, (empty) (empty)(empty) ( half full ) ( half full ) ( half full ) ( full ) ( full ) ( full ) : 4.5 units of gold, and we need to share it equally... like that?


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#672 2011-06-23 01:05:59

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

Yes. Each one would now need to get 1.5 units of gold and 3 sacks.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

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#673 2011-06-23 01:13:23

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Hi bobbym,

Okay, thanks.

Let me check:
n=1, 0 ways.
n=2, 3 ways.
n=3, 1 way
?


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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#674 2011-06-23 01:20:39

bobbym
bumpkin
From: Bumpkinland
Registered: 2009-04-12
Posts: 109,606

Re: Is this cool with you?

Hi gAr;

I do not have a working program for this yet. The one I was using had a bug in it so I have to rewrite it. I do not have a table of answers yet.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
Always satisfy the Prime Directive of getting the right answer above all else.

Offline

#675 2011-06-23 01:25:23

gAr
Member
Registered: 2011-01-09
Posts: 3,482

Re: Is this cool with you?

Okay.
But these small cases can be done by hand.
I'm asking to verify whether I understood it correctly.


"Believe nothing, no matter where you read it, or who said it, no matter if I have said it, unless it agrees with your own reason and your own common sense"  - Buddha?

"Data! Data! Data!" he cried impatiently. "I can't make bricks without clay."

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