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#1 2014-07-02 12:31:00

Agnishom
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From: The Complex Plane
Registered: 2011-01-29
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Even more trig

If sin(B+C-A),sin(C+A-B) and sin(A+B-C)are in A.P.; then cot A,cot B,cot C are in -
(a)  GP
(b)  HP
(c)  AP
(d)  None of these.


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#2 2014-07-14 04:19:24

Nehushtan
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Re: Even more trig

We have

dunno


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#3 2014-07-14 04:49:48

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

M says b. I haven't gotten to the solution analytically yet, though.


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#4 2014-07-14 04:59:17

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 84,194

Re: Even more trig

Hi;

May I see what you did with M to get that?


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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#5 2014-07-14 05:01:47

anonimnystefy
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Posts: 15,184

Re: Even more trig

Sure!

FullSimplify[Sin[b + c - a] + Sin[a + b - c] == 2 Sin[a + c - b]]

2 Cos[a] Cos[c] Sin[b] == Cos[b] Sin[a + c]

Last edited by anonimnystefy (2014-07-14 05:02:14)


“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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#6 2014-07-14 05:12:48

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 84,194

Re: Even more trig

I do not understand it.


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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#7 2014-07-14 05:18:44

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

What do you not understand? I just rearranged the result a bit and got the answer.


“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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#8 2014-07-14 05:20:56

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 84,194

Re: Even more trig

They are in AP?


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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#9 2014-07-14 05:22:00

anonimnystefy
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From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

The cot's are in HP.


“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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#10 2014-07-14 05:26:16

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 84,194

Re: Even more trig

How are you representing the sines in AP is what I meant?


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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#11 2014-07-14 05:31:10

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

The same as Nehushtan did.


“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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#12 2014-07-14 05:32:36

bobbym
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From: Bumpkinland
Registered: 2009-04-12
Posts: 84,194

Re: Even more trig

Okay, I see what you saying.


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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#13 2014-07-14 05:39:03

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

Now to do it by hand...


“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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#14 2014-07-14 05:46:37

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,194

Re: Even more trig

You have the result, now you just have to back engineer the how.


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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#15 2014-07-14 05:52:56

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

I think I figured it out. I will post it when I write it out.


“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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#16 2014-07-14 06:07:10

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

Here's the solution.


“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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#17 2014-07-14 06:16:13

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 84,194

Re: Even more trig

Hi;

Got to get off, will look at it when I get back. You did good.


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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#18 2014-07-14 06:21:17

gAr
Member
Registered: 2011-01-09
Posts: 3,478

Re: Even more trig

Expanding gives:

hence in H.P.


"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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#19 2014-07-14 06:27:55

anonimnystefy
Real Member
From: The Foundation
Registered: 2011-05-23
Posts: 15,184

Re: Even more trig

Hi bobbym

See you later!

Thanks.

Last edited by anonimnystefy (2014-07-14 06:29:01)


“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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