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#1 2014-05-14 04:29:27

Agnishom
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From: Riemann Sphere
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(Less than) 21 Trig Questions from Amrita

1. If sin(π cos(θ))= cos(π sin(θ)), Find sin 2θ

Last edited by Agnishom (2014-05-14 12:01:53)


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#2 2014-05-14 05:22:58

anonimnystefy
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From: Harlan's World
Registered: 2011-05-23
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Re: (Less than) 21 Trig Questions from Amrita

I don't think that one can be solved analytically.


“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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#3 2014-05-14 05:52:29

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

Re: (Less than) 21 Trig Questions from Amrita

Hi anonimnystefy;


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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#4 2014-05-14 06:37:50

anonimnystefy
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From: Harlan's World
Registered: 2011-05-23
Posts: 16,049

Re: (Less than) 21 Trig Questions from Amrita

It does not do anything.

I found one solution using FindInstance:


“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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#5 2014-05-14 06:46:55

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

Re: (Less than) 21 Trig Questions from Amrita

Hi;


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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#6 2014-05-14 07:57:47

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
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Re: (Less than) 21 Trig Questions from Amrita

What is reduce supoosed to do?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#7 2014-05-14 07:58:36

ShivamS
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Registered: 2011-02-07
Posts: 3,648

Re: (Less than) 21 Trig Questions from Amrita

Reduce[expr, vars] reduces the statement expr by solving equations or inequalities for vars and eliminating quantifiers.

http://reference.wolfram.com/mathematic … educe.html

Last edited by ShivamS (2014-05-14 08:16:16)

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#8 2014-05-14 10:59:30

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

Re: (Less than) 21 Trig Questions from Amrita

That is correct. It can get more general answers then Solve can.


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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#9 2014-05-14 12:02:24

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
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Re: (Less than) 21 Trig Questions from Amrita

I've updated post 1. Is it analytically doable now?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#10 2014-05-15 20:22:59

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
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Re: (Less than) 21 Trig Questions from Amrita

But that is not true;

It is an incorrect formula.

Please keep this forum clean. The administrator will probably ban you soon.


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#11 2014-05-15 20:29:38

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
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Re: (Less than) 21 Trig Questions from Amrita

Why do you use a phoney email?

By the way, thanks for helping. Could you do the rest?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#12 2014-05-15 21:02:04

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

Re: (Less than) 21 Trig Questions from Amrita

I only came up with 1 composition formula, it was too complicated.


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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#13 2014-05-15 21:07:33

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
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Re: (Less than) 21 Trig Questions from Amrita

Quinn gave me this formula:

2 sin x cos x = sin 2 x


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#14 2014-05-15 21:11:29

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

Re: (Less than) 21 Trig Questions from Amrita

So, what does that do?


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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#15 2014-05-15 21:19:34

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
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Re: (Less than) 21 Trig Questions from Amrita

Post 1 ends with

Find sin 2θ


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#16 2014-05-15 21:20:53

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

Re: (Less than) 21 Trig Questions from Amrita

So it does, there are a lot of identities involving sin 2θ.


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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#17 2014-05-16 01:02:32

Agnishom
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From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
Website

Re: (Less than) 21 Trig Questions from Amrita

May I post question 2?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

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#18 2014-05-16 01:03:37

ShivamS
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Registered: 2011-02-07
Posts: 3,648

Re: (Less than) 21 Trig Questions from Amrita

No, you are not allowed to.

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#19 2014-05-16 01:07:20

Agnishom
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From: Riemann Sphere
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Posts: 24,974
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Re: (Less than) 21 Trig Questions from Amrita

Why?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

Offline

#20 2014-05-16 01:07:38

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

Re: (Less than) 21 Trig Questions from Amrita

I agree, post #3.


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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#21 2014-05-16 01:08:34

ShivamS
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Registered: 2011-02-07
Posts: 3,648

Re: (Less than) 21 Trig Questions from Amrita

Agnishom wrote:

Why?

Why would you even ask to ask?

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#22 2014-05-16 01:11:44

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

Re: (Less than) 21 Trig Questions from Amrita

What he could do is rename #2 to #3.


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

#23 2014-05-16 02:37:52

Agnishom
Real Member
From: Riemann Sphere
Registered: 2011-01-29
Posts: 24,974
Website

Re: (Less than) 21 Trig Questions from Amrita

What is this #2  and #3?


'And fun? If maths is fun, then getting a tooth extraction is fun. A viral infection is fun. Rabies shots are fun.'
'God exists because Mathematics is consistent, and the devil exists because we cannot prove it'
I'm not crazy, my mother had me tested.

Offline

#24 2014-05-16 02:40:48

ShivamS
Member
Registered: 2011-02-07
Posts: 3,648

Re: (Less than) 21 Trig Questions from Amrita

Post numbers.

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#25 2014-05-16 03:47:45

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

Re: (Less than) 21 Trig Questions from Amrita

Yes, post the third question second and the second question 12th... Jumble them up like that and then post #12 is answered.


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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