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#26 2013-05-30 03:21:06

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Hi bobbym

Last edited by anonimnystefy (2013-05-30 03:21:18)


“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

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#27 2013-05-30 03:29:40

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

Hi;


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

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#28 2013-05-30 03:37:29

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Hi


“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

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#29 2013-05-30 03:41:40

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

Hi;


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#30 2013-05-30 03:46:22

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Hi


“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

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#31 2013-05-30 03:48:54

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

Hi;


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#32 2013-05-30 03:50:14

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Hi


“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

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#33 2013-05-30 03:57:19

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

That long side has to have an altitude of greater than 83.

View Image: 2013-05-30_085524.gif

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#34 2013-05-30 04:00:30

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Why is that?


“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

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#35 2013-05-30 04:01:58

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

Because from that vertex on the left to the side all the way on the right can not be 83.

I have a much smaller triangle.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#36 2013-05-30 04:05:40

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Hi

But, the altitude is not calculated like that. It is the distance of that point from the whole line that goes through the other two.

orthocenter_obtuse.jpg


“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

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#37 2013-05-30 04:09:23

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

That is the incenter. The altitude goes from a vertex to an opposite side making a right angle with that side. It is obvious from the point on the left to the side on the extreme right is greater than 499 and less than 582.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#38 2013-05-30 04:11:49

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Um, no, that is not the incenter. Did you see the picture above. The red dashed lines are all altitudes.


“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

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#39 2013-05-30 04:20:17

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

Where the three altitudes meet is called the orthocenter. But that is not important.

What is your definition of an altitude.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#40 2013-05-30 04:22:16

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

It is the line which goes through a vertex of a triangle and is perpendicular to the side of the triangle which is opposite to that vertex.


“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

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#41 2013-05-30 04:30:25

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

Excuse the crudity of that drawing. I hastily just joined line segments to make a rough triangle.

How can you say that EG which is an attempt at an altitude is 83 in length?

View Image: 2013-05-30_085524.gif

In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#42 2013-05-30 04:31:26

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

EG is not the altitude. The altitude of the triangle that goes through E is outside the triangle.


“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

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#43 2013-05-30 04:34:43

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

Please show your triangle.

But keep in mind, mine is smaller that yours. There may be many such triangles.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#44 2013-05-30 04:46:23

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

There is only one triangle with sides 12, 14 and 83.

The picture is attached below. ABC is the triangle and AD is the altitude.

View Image: triangle_altitudes.png

“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

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#45 2013-05-30 05:01:04

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

You mean with altitudes of 12, 14, 83.

That sounds correct but now I know where the problem is. My method does not need the sides of the triangle.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#46 2013-05-30 05:06:08

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Yes, altitudes.

Have you seen the picture?

What do you mean, your method doesn't need sides?


“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

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#47 2013-05-30 05:13:03

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

There was a page that I thought I bookmarked that gave me the relationships in terms of inequalities.


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#48 2013-05-30 05:17:06

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

Between?

And, what exactly are we doing now. We have the value, we have constructed the triangle. What else is there to do?


“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

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#49 2013-05-30 05:21:58

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 81,431

Re: triangle inequality

The lower bound:

The upper bound:


In mathematics, you don't understand things. You just get used to them.
I have the result, but I do not yet know how to get it.
All physicists, and a good many quite respectable mathematicians are contemptuous about proof.

Online

#50 2013-05-30 05:24:26

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 14,812

Re: triangle inequality

That is what I have too for the upper bound. Haven't done the lower bound, but it seems correct.


“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

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