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waterineyes Group TitleBest ResponseYou've already chosen the best response.8
Let us start from the start..
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.0
it is cos^2...ok
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.1
\[cos^{2}2x cos^{2}6x = sin4xsin8x\]?
 2 years ago

Mimi_x3 Group TitleBest ResponseYou've already chosen the best response.1
have you tried cos^{2}2x = (1+cos4x)/2?
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
\[\cos^2 A  \cos^2 B = \sin(A+B)\sin(BA)\] This is a standard formula. So, we need a proof right?
 2 years ago

Mitul Group TitleBest ResponseYou've already chosen the best response.0
(1+cos4x)/2(1+cos12x)/2 = (1+cos 4x+cos12x+cos4xcos12x)/2 and then defactorize the last term...and factorize the second and third term
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.0
@apoorvk yup proof needed..
 2 years ago

Mitul Group TitleBest ResponseYou've already chosen the best response.0
@apoorvk it is cosAcosBand not their squares for standard formula
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
\[\cos^2(2x)  \cos^2(6x) \implies (\cos(2x)  \cos(6x))(\cos(2x) + \cos(6x))\] So: Using: \[\cos(C) + \cos(D) = 2\cos(\frac{C+ D}{2})\cos(\frac{CD)}{2})\] \[\cos(C)  \cos(D) = 2\sin(\frac{C+ D}{2})\sin(\frac{DC}{2})\] \[(2\sin(4x) \sin(2x))(2\cos(4x)\cos(2x)) \implies (2\sin(2x)\cos(2x)) \cdot (2\sin(4x) \cos(4x))\] \[\implies \sin(4x) \cdot \sin(8x)\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
Using: \[2\sin(x)\cos(x) \implies \sin(2x)\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
I think above you by mistake written (BA) @apoorvk
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
You are doing wrong I guess..
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
Rewrite for cos(A)  cos(B) = ??
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.0
@apoorvk u told me it is sin(a+b).sin(ba) but u have written differ
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
yeah I have memory problems . Amnesia *sigh* *sniff*
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
\[\cos(A)  \cos(B) = 2\sin(\frac{A+B}{2}) \cdot \sin(\frac{BA}{2})\]
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
And not sin(aB) in the last..
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.0
@apoorvk if i use ur method we wont get that lol
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
NOOOOOOOO!!!!!!!!!!!!!!!!!! What have i been doing? /_\
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
Okay please tweak it and use it as needed, we know the procedure atleast. Or should I repost?
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
See: \[\cos^2(2x)  \cos^2(6x) = \sin(A+B)\sin(AB) \implies \sin(2x  6x)\sin(2x + 6x)\] Don't you think we get negative ??? @apoorvk
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
yeah i got it ate already  unfortunately i can't view my raw LateX codes (some stupid bug :\), so I'll have to edit it manually. NOOOOOO!!!!!!!!!
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
Sir what you think is correct, if you want a confirmation. .
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
There must be condition for doing this formula : I am discussing with you @apoorvk
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
The above said formula will work if B > A..
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
\[\cos^2A−\cos^2B\] \[=(\cos A+\cos B)(\cos A−\cos B)\] \[=[2\cos(\frac{A+B}2)\cos(\frac{A−B}2)][2\sin(\frac{A+B}2)\sin(\frac{BA}2)]\] \[=[2\sin(\frac{A+B}2)\cos(\frac{A+B}2)][2\sin(\frac{BA}2\cos(\frac{BA}2)]\] \[=\Large\boxed{\sin(A+B)\sin(BA)}\] Happy nitpickers? ____
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
Do you think It will work ??
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
Water in eyes, Fish in Water \(\large \rightarrow\) so Fish in eyes. _
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
I am asking you @apoorvk
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
If fish is eyes then why are looking upwards?? Is fish in your eyes??
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
I paarsonaaally bilib it's Phaathar bill waark! , (dish phormula)
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
What is this?? @apoorvk
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
U know aandarishtand? oowhaat u know no inglis?? BAH HUMBUG!
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
Inglish pipul go, liebe children behind _
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
'Addition', man, addition > " sin (A '+' B)  Y U LOVE SUBTRACTION??
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
Okay my mistake..
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
U inglish phail, I inglish oowhale. ____
 2 years ago

waterineyes Group TitleBest ResponseYou've already chosen the best response.8
You failed in english? ok I got this.. Better luck next time.. @apoorvk
 2 years ago

apoorvk Group TitleBest ResponseYou've already chosen the best response.1
Hu shaid I phail in inglish?? U no si mai bandarfool inglish haan??? o.O I gets the 105 out of 100 __ u get how many?
 2 years ago
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