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#26 2014-05-16 04:06:59
Re: (Less than) 21 Trig Questions from Amrita
I haven't got a clue of what you are talking about?
'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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#27 2014-05-16 04:09:04
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: (Less than) 21 Trig Questions from Amrita
A joke, I am kidding you. Of course you can post the 2nd one.
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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#28 2014-05-17 04:08:57
- gourish
- Member
- Registered: 2013-05-28
- Posts: 153
Re: (Less than) 21 Trig Questions from Amrita
shouldn't sin2θ= -3/4 cause that's quite easy to solve by using inverse trignometric functions (i assumed the angles to be in the principal branches) then what's the problem in finding it?
"The man was just too bored so he invented maths for fun"
-some wise guy
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#29 2014-05-17 04:12:06
Re: (Less than) 21 Trig Questions from Amrita
Please tell me how to do this.
'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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#30 2014-05-17 04:52:11
- gourish
- Member
- Registered: 2013-05-28
- Posts: 153
Re: (Less than) 21 Trig Questions from Amrita
Agnishom,
try using the inverse trignometric functions on the equality maybe it will help....
"The man was just too bored so he invented maths for fun"
-some wise guy
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#31 2014-05-17 04:56:49
- gourish
- Member
- Registered: 2013-05-28
- Posts: 153
Re: (Less than) 21 Trig Questions from Amrita
the equality sin(pie sinθ ) = cos(pie cosθ )
on applying arc sine on both sides becomes pie sinθ = pie/2 -(pie cosθ ) now shift the terms on the same side and divide throught by pie
you get sinθ + cosθ =1/2 and then square both sides to get 1+2sinθ cosθ =1/4 and then solving 2sinθ cosθ =-3/4
and we already know that 2sinθ cosθ = sin2θ
"The man was just too bored so he invented maths for fun"
-some wise guy
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#32 2014-05-17 06:04:55
- Bob
- Administrator
- Registered: 2010-06-20
- Posts: 10,621
Re: (Less than) 21 Trig Questions from Amrita
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob 
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#33 2014-05-17 06:16:05
- Bob
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Re: (Less than) 21 Trig Questions from Amrita
Checked numerically and both answers work.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#34 2014-05-17 11:26:50
- anonimnystefy
- Real Member
- From: Harlan's World
- Registered: 2011-05-23
- Posts: 16,049
Re: (Less than) 21 Trig Questions from Amrita
Hi Bob
I tried doing the problem again. I am getting -3/4 only.
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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#35 2014-05-17 19:32:33
- Bob
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- Registered: 2010-06-20
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Re: (Less than) 21 Trig Questions from Amrita
hi Stefy,
Using Gourish's method I agree. Mine was much longer and 'round the houses'. Because inv trig are multi valued there are several places where new 'answers' may pop up. If you try +3/4 as a solution it works. I haven't decided why this happens yet but I'm pre-occupied with sorting out spam at the moment.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#36 2014-05-17 19:55:08
Re: (Less than) 21 Trig Questions from Amrita
Thank You, gourish.
bob bundy, Why are we having so much spam today?
'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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#37 2014-05-17 20:30:22
- Bob
- Administrator
- Registered: 2010-06-20
- Posts: 10,621
Re: (Less than) 21 Trig Questions from Amrita
Edited
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#38 2014-05-17 20:31:05
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: (Less than) 21 Trig Questions from Amrita
My defenses are down. We have stopped them temporarily.
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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#39 2014-05-17 20:32:28
- Bob
- Administrator
- Registered: 2010-06-20
- Posts: 10,621
Re: (Less than) 21 Trig Questions from Amrita
Welcome back! Am I glad to see you.
Bob
Children are not defined by school ...........The Fonz
You cannot teach a man anything; you can only help him find it within himself..........Galileo Galilei
Sometimes I deliberately make mistakes, just to test you! …………….Bob
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#40 2014-05-17 20:40:30
- Amrita
- Member
- From: Westing's House
- Registered: 2014-04-30
- Posts: 848
Re: (Less than) 21 Trig Questions from Amrita
Hello everybody!
In mathematics the art of proposing a question must be held of higher value than solving it.
- Georg Cantor (1845-1918)
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#41 2014-05-17 20:42:17
Re: (Less than) 21 Trig Questions from Amrita
Hi Amrita;
Did you like the upgrade?
'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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#42 2014-05-17 20:43:06
- bobbym
- bumpkin
- From: Bumpkinland
- Registered: 2009-04-12
- Posts: 109,606
Re: (Less than) 21 Trig Questions from Amrita
Hi Bob and all.
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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#43 2014-05-17 20:44:18
- Amrita
- Member
- From: Westing's House
- Registered: 2014-04-30
- Posts: 848
Re: (Less than) 21 Trig Questions from Amrita
Yes,I liked it.
In mathematics the art of proposing a question must be held of higher value than solving it.
- Georg Cantor (1845-1918)
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#44 2014-05-17 20:45:44
Re: (Less than) 21 Trig Questions from Amrita
Did you go to Profile > Display > Set style to air as I told you in the other thread?
'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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#45 2014-05-17 20:47:23
- Amrita
- Member
- From: Westing's House
- Registered: 2014-04-30
- Posts: 848
Re: (Less than) 21 Trig Questions from Amrita
Yes,I did that too Mr.Chattopadhyay.
In mathematics the art of proposing a question must be held of higher value than solving it.
- Georg Cantor (1845-1918)
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#46 2014-05-17 20:50:16
Re: (Less than) 21 Trig Questions from Amrita
Did you understand gourish's solution?
'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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#47 2014-05-17 20:51:24
- Amrita
- Member
- From: Westing's House
- Registered: 2014-04-30
- Posts: 848
Re: (Less than) 21 Trig Questions from Amrita
Plz explain it once more for me,will u?
In mathematics the art of proposing a question must be held of higher value than solving it.
- Georg Cantor (1845-1918)
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#48 2014-05-17 20:52:24
Re: (Less than) 21 Trig Questions from Amrita
Sure, give me 5 minutes...
'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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#49 2014-05-17 21:03:50
Re: (Less than) 21 Trig Questions from Amrita
sin(π cos(θ))= cos(π sin(θ))
Or, sin(π cos(θ))= sin(90° - π sin(θ))
Let us assume that theta is in the first quadrant:
π cos(θ) = 90° - π sin(θ)
Or, π cos(θ) + π sin(θ) = 90°
Dividing both sides by π :
cos(θ) + sin(θ) = 0.5 [Since π is 180 Degrees]
Squaring both sides,
cos^2(θ) + sin^2(θ) + 2cosθsinθ = 0.5
Or, 1 + 2cosθsinθ = 0.5
Or, 2cosθsinθ = 0.5 - 1 = -0.5
Thus, sin2θ = 2cosθsinθ = -0.5
Wait, what? That is not supposed to be the answer, what did I do wrong??!
Last edited by Agnishom (2014-05-17 21:04:51)
'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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#50 2014-05-17 21:18:22
- Amrita
- Member
- From: Westing's House
- Registered: 2014-04-30
- Posts: 848
Re: (Less than) 21 Trig Questions from Amrita
I could'nt understand what did u do.
In mathematics the art of proposing a question must be held of higher value than solving it.
- Georg Cantor (1845-1918)
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