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I feel like a fool having to ask, but for some reason I'm going around and around with this one without coming to an answer.

x/(x-1) = y

How do I solve for x? I'm just hitting some stupid mental block here.

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Eschew obfuscation, espouse elucidation.

Hi David,

(x-1)/x = 1/y

1-(1/x) = 1/y

1/x = 1-(1/y)

1/x = (y-1)/y

So the answer is :

x = y / (y-1)

MMmmmh, maths ... so exciting

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Christophe Grellier

For x=10 ,y= 1.11111...
For X=100 ,y= 1.0101...
For X=1000 ,y= 1.001001...
For x=10,000 .y= 1.0001001...
So the answer takes the form of a graph. If I remember correctly(it's been a while)?

Reminds me of Fractals and chaos theory

http://www.fractalwisdom.com/FractalWisdom/fractal.html

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

Problem is I can't remember if x=1 would make it all wrong...

1/(1-1)=y (can't divide by zero)

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

The graph looks like that :

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Christophe Grellier

Is that, for all x, such that x~=1

http://en.wikipedia.org/wiki/Division_by_zero#Extended_real_line

Set theory?

It really has been a long long time since a symbolic logic class caused a little curiosity towards Boolean alg and such.

I have mind probs(memory and concentration) I tend to feel my way now...

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

Thanks Christophe! That's it. Last night I was going in circles in entirely the wrong direction. No more math after midnight on weekends for me.

Thanks again.

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Eschew obfuscation, espouse elucidation.

Sounds like an exciting evening....... Well at least you didn't lose your pocket protector.....

Oh man I am in trouble now.....

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Ann Arbor Guitars

Okay, I just had to go through it again to make sure I wasn't loosing it. Though the answer was certainly right, I had to factor through in my own way.

x / (x-1) = y

x = y (x-1)

x = xy-y

x-xy = -y

x (1-y) = -y

x = -y / (1-y)

x = y / (y-1)

Same answer. I like how you go through it without crossing the variables back and forth, but for some reason this way seems a bit more tangible to me.

Of course now I've had "Lobachevsky" going through my head all last night and this morning (for all you Tom Lehrer fans out there).

Thanks again.

Hesh - I lost my favorite calculator at the Cooper's Glen festival (my main calculator for almost 10 years). I just got a new one yesterday, and have been going through withdrawal. This is very important therapy.....

_________________
Eschew obfuscation, espouse elucidation.

Hyperbolic geometry?

Dang, I was hoping I was looking at a fuzzy logic set , (rate of change)...
Dang, just a fuzzy brain #*@!....

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

Hyperbolic poetry?

There once was a man, Nagyvary
Who aimed to resolve an old query
So he whipped out his lucci
Checked from Helmholtz to Chladni
-At the store, just to find the best berry!

Then he took it on home right that instant
Pressed it right before starting to ferment
Took a sip, then a belch
Said "Look out Mr. Welch!"
This great formula's covered by patent!

How does this concern Stradivari?
Well we're talking of sly Nagyvary
Who found in the shellac
Just a small tiny spack
Tony's drool with a trace of mulberry!

Now THAT's the secret to Stradivarius' tone.

attrib to Dave Collins...

Why did you take your calc(T.I. 85?) to a music festival?

Thanks Christophe for graphing it, looks elegant and exclamatory at the same time to me.

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

No, the simpler TI 30xIIa. Had most of what I used on a regular basis though.

I don't get the question though. How could anyone go to a music festival without taking their calculator???

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Eschew obfuscation, espouse elucidation.

Hewlett Packard and reverse polish notation RULES!!! <smile>

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Formerly known as Adaboy.......

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

The allegro found in the user gallery brings it back to stringed instruments. sort of.

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"It's a Tone Faerie thing"
"Da goal is to sharpen ur wit as well as ye Sgian Dubh"
"Sippin Loch Dhu @Black lake" ,Kirby O...

I think it is called a trancendental function. it is 1/x +1/y = 1

Mike

Here you go David.

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The member formerly known as erikbojerik....