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**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Hi bobbym,

That's okay, found the link.

"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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

I have provided the picture in post #1201. I still get the same answer.

[Picture removed by administrator]

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

"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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

I too did something like that.

I had seen a similar problem in brilliant, but in its current format it would be impossible to find!

"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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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

I do not like the new format at Brilliant. I liked the old one better.

**In mathematics, you don't understand things. You just get used to them.**

**I agree with you regarding the satisfaction and importance of actually computing some numbers. I can't tell you how often I see time and money wasted because someone didn't bother to run the numbers.**

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**gAr****Member**- Registered: 2011-01-09
- Posts: 3,479

Me neither. I rarely go there now, it's not possible to keep track of the problems and discussions there, just looks like a flash flood of questions!

Logging off, see you later..

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

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

Hi gAr;

It is a shame! Many people complained but no one is listening.

Have a good night. See you tomorrow.

**In mathematics, you don't understand things. You just get used to them.**

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

**New question:**

**A circle is inscribed in a square with sides of 10 and a quadrant circle with radius 10 overlaps as shown in the drawing. What is the area of the red region?**

**A says) Exactly 1. Saw your answer B, as usual it was wrong.**

**B says) That is somewhat close there A, you are getting better.**

**C says) I got the right answer and it agrees with A.**

**A says) Bravo C!**

**D says) I got B's answer.**

**E says) I got around .7**

**What did you get?**

**In mathematics, you don't understand things. You just get used to them.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi Bobby,

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

Hi phrontister;

**In mathematics, you don't understand things. You just get used to them.**

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**anonimnystefy****Real Member**- From: The Foundation
- Registered: 2011-05-23
- Posts: 15,889

Hi bobbym

I am getting

*Last edited by anonimnystefy (2014-02-25 01:47:42)*

Here lies the reader who will never open this book. He is forever dead.

Taking a new step, uttering a new word, is what people fear most. ― Fyodor Dostoyevsky, Crime and Punishment

The knowledge of some things as a function of age is a delta function.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

Hi;

**In mathematics, you don't understand things. You just get used to them.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi,

This is how I went about it in Geogebra - which is pretty close to stefy's.

That other answer I got in my previous post - which was also pretty close to stefy's - used the fractions given in Geogebra's 'Exact evaluation' from their CAS, but I take it that if stefy's is the right answer then Geogebra may not be truly 'exact'...although we agree for many decimal places.

*Last edited by phrontister (2014-02-25 03:12:51)*

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

Hi phrontister;

**In mathematics, you don't understand things. You just get used to them.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi Bobby,

"The good news about computers is that they do what you tell them to do. The bad news is that they do what you tell them to do." - Ted Nelson

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

Hi;

Your progress with it has been excellent. True, there are zillions of files and the demonstrations are incredible but to get through them requires a studious mind. Wunderbar!

**In mathematics, you don't understand things. You just get used to them.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi Bobby,

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

Hi;

**In mathematics, you don't understand things. You just get used to them.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi Bobby,

This is what I did (had to research the lune idea first as I'd never heard of it before, but I came across the term in searching for 'crescent', and then used Wolfram's lune formula):

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

You solved it using the lune! I was unable to and had to use the left region.

**In mathematics, you don't understand things. You just get used to them.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

It's a horrible-looking formula and I'll never try to understand it! But it worked beautifully and shrank down a lot when simplified.

Here is the link.

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**bobbym****Administrator**- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 92,878

Yes, I was there. Can you show me your M workings that I can follow. That page drove me crazy.

**In mathematics, you don't understand things. You just get used to them.**

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

Hi Bobby,

Here is a much better version of my M explanation (I deleted the previous one), plus an amended drawing to suit it:

*Edit: There's now an amended version of this amended drawing in my next post...*

*Last edited by phrontister (2014-02-26 21:27:36)*

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**phrontister****Real Member**- From: The Land of Tomorrow
- Registered: 2009-07-12
- Posts: 3,979

I made a mistake with the formula for IC on my last drawing...so here's the update.

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