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

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

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

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

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

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

sasogeek
 2 years ago
Best ResponseYou've already chosen the best response.0use 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.

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

sasogeek
 2 years ago
Best ResponseYou've already chosen the best response.0earlier 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

sasogeek
 2 years ago
Best ResponseYou've already chosen the best response.0i 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

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

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

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

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

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

mathslover
 2 years ago
Best ResponseYou've already chosen the best response.2cos 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!

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

Yahoo!
 2 years ago
Best ResponseYou've already chosen the best response.12Sin54.cos7  2sin18cos7 2cos7 ( sin54  sin18) sin54 = cos 36 2cos7(cos36  sin18) 2cos7( (sqrt5 + 1)/2  (sqrt51)/2) = cos7

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

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

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