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mathslover
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Find the value of : sin 47 (degrees) + sin 61 (degrees)  sin 11 (degrees)  sin 25 (degrees)
 2 years ago
 2 years ago
mathslover Group Title
Find the value of : sin 47 (degrees) + sin 61 (degrees)  sin 11 (degrees)  sin 25 (degrees)
 2 years ago
 2 years ago

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1on1 Group TitleBest ResponseYou've already chosen the best response.0
set the calculator to degrees and start pressing buttons
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
lol @1on1 , that's a shortcut but I do want to do that without *calculator*
 2 years ago

1on1 Group TitleBest ResponseYou've already chosen the best response.0
Sorry, that will require much more thought from me !
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
No problem! @sasogeek any suggestions, if no then I have only 1 .
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
Not suggestion but an idea infact.
 2 years ago

sasogeek Group TitleBest ResponseYou've already chosen the best response.0
use the calculator to find their actual values and do normal addition... that's if u want to do some work... if not, u may use the calculator to find the whole answer.
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
hmn quite hard if calculator is not allowed.
 2 years ago

sasogeek Group TitleBest ResponseYou've already chosen the best response.0
earlier i thought it was sin(A+B)sin(AB) sort of question but it's not, direct solution with the calculator is the way forward :) unless u know those values off the top of ur head xD
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
xD thanks though
 2 years ago

sasogeek Group TitleBest ResponseYou've already chosen the best response.0
i do not wish to confuse you, but you may want to read this, http://www.trans4mind.com/personal_development/mathematics/trigonometry/sumProductCosSin.htm#Sum_of_Sine_and_Cosine
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.1
@mathslover Do u knw the Value of Sin18 and cos36
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.1
SinA + SinB = 2Sin (A+B)/2 . Cos (AB)/2...Use this
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
@Yahoo! and @sasogeek this was my main idea.
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
Let me try again to find out the answer through the formula of sina + sinb
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
OK so if I remember the values of : cos 36 degrees and sin 18 degrees then I am getting cos 7 degrees.
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
cos Here is it how I did that : \[\large{\sin 47 + \sin 61 = 2 \sin 54 \cos 7 }\] ^that theta(s) are in degrees. similarly : \[\large{(\sin 11 + \sin 25) = ( 2\sin 18 \cos 7)}\] from the above we get : \(2\cos 7 ( \sin 54  \sin 18 )\) \(2\cos 7 ( 2\cos 36 \sin 18)\) \(4\cos 7 (\frac{\sqrt{5}+1}{4} \times \frac{\sqrt{5}1}{4})\) \(\cos 7\) That is it! Is it correct? @sasogeek @Yahoo!
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.1
Yup...thats wat i also Got
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.1
2Sin54.cos7  2sin18cos7 2cos7 ( sin54  sin18) sin54 = cos 36 2cos7(cos36  sin18) 2cos7( (sqrt5 + 1)/2  (sqrt51)/2) = cos7
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.1
Sorry 2cos7( (sqrt5 + 1)/4  (sqrt51)/4)
 2 years ago

mathslover Group TitleBest ResponseYou've already chosen the best response.2
np, thanks a lot for your help yahoo.
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.1
Welcome....)...
 2 years ago

Yahoo! Group TitleBest ResponseYou've already chosen the best response.1
To..Be honest..U Did All the Hard Work..)
 2 years ago
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