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anonymous
 5 years ago
use a double angle identity to find the exact value
sin22.5^ocos22.5^o
anonymous
 5 years ago
use a double angle identity to find the exact value sin22.5^ocos22.5^o

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anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0why I am still at 19 fans, after spending the last 5 hours working my *** out?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0if you help me with this i will become a fan

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0the double angle identities are as follows: \[\cos (A  B) = (\cos A)(\cos B) + (\sin A)(\sin B) \] \[\cos (A + B) = (\cos A)\cos B  (\sin A)\sin B \] \[\sin (A + B) = (\sin A)(\cos B) + (\cos A)(\sin B) \] \[\sin (A  B) = (\sin A)(\cos B)  (\cos A)(\sin B) \] alright andy :) you can lead from here ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0hmm, am I mixing it all up with the double angle identities? those are the sin and cos indentities , hmm, please correct me if I'm wrong ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0double angle identities go like this, egzample: sin(2x)=2sinxcosx

nowhereman
 5 years ago
Best ResponseYou've already chosen the best response.0That is just the above with setting A=B

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0no the identities are sin2A=2sineAcosA cos2Acos^2Asin^2A =12sin^2A =2cosA1

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0or right lol , thank you, alright angoo, give it a try ^_^

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ok I am bad at this, I guess I must have skipped school the day this stuff was tought

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0nah, stary, you go ahead, I dont get this stuff yet

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0ask your beloved google lol

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0well, Google can give me examples, and explanations, and I can learn from them, but it would take too much time... so just go ahead and do it mimi

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0this is my new signature btw: ▓▒░╔ᴧᴨᴅᴙiᴜs╖░▒▓

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0alright LoveL , let me get this clear : you want to find the answer of : sin(22.5)cos(22.5)? or do you want to find the exact angle for sin(22.5)=? or cos(22.5)=? ^_^ lol, it's filled with mystery, but I like it :)

nowhereman
 5 years ago
Best ResponseYou've already chosen the best response.0I will show you, first of all: \[\sin (22.5^\circ)\cos(22.5^\circ) = \sin(\frac{180^\circ}{8})\cos(\frac{180^\circ}{8}) = \sin(\frac{π}{8})\cos(\frac π 8)\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0nvm, follow up with nowhereman ^_^ he'll lead you through.

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0so, loveinglife, do you feel happy today? because I do, but I could become even more happy if you gift me a fan =D In that case, I will give you a fan too, so you become a lifesaver, and I become a superstar, a clear winwin =D

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0LOL, and you're still on it

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0@BecomeMyFan im your fan now. thank you for trying

nowhereman
 5 years ago
Best ResponseYou've already chosen the best response.0Then \[\sin(\frac π 8)\cos(\frac π 8) = \frac 1 2 \cdot \left(2\sin(\frac π 8)\cos(\frac π 8)\right)\] Thus by applying that double arc formula on the inner part (in reverse direction if you want) you get \[=\frac 1 2 \sin(2\frac π 8) = \frac 1 2\sin(\frac π 4) = \frac 1 4 \sqrt 2\]

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0Oh my god your awesome. thank you soo much you just saved my trig grade

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0love, are you in highschool?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0because if you are doing this stuff in high school, I must have skipped ALOT of it

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0im saddly in college and i thought i was good in math till i got here

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0why am I still a mear star?

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0I wanna be a superstar

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0it was supposed to rhyme

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0sorry cant help you there but im done, but i will probably be back at some point

anonymous
 5 years ago
Best ResponseYou've already chosen the best response.0it is part of a poem I am writting about OpenStudy
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