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#1 2014-05-14 04:29:27
(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
- bumpkin
- 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
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
- Member
- 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
- bumpkin
- 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
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
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
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
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
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
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
- Member
- 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
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.
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#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
- Member
- Registered: 2011-02-07
- Posts: 3,648
Re: (Less than) 21 Trig Questions from Amrita
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.
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#23 2014-05-16 02:37:52
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.
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#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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