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anonymous
 one year ago
Find an exact value.
sine of negative eleven pi divided by twelve.
anonymous
 one year ago
Find an exact value. sine of negative eleven pi divided by twelve.

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welshfella
 one year ago
Best ResponseYou've already chosen the best response.0sien 11 p / 12 now we can find the value of sine of 11pi/ 6 which is half of 11pi/12

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0dw:1438258865764:dw

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0 sin 11pi/6 = sin pi/6 = 1/2

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0sin(11pi+pi/6)=1/2 so, sin(11/12)=....

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0now to find sin 11pi/12 we using the half angle formula sin 11pi/12 = sin pi/6  1 + cos pi/6

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0i'll just check that is ok   im relying on my memory here

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0wait I'm still a little lost

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0oops sorry thats the halfangle tan formula

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0i mad a mistake there where are you lost?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0well I wouldn't say lost, I was here for this lecture and I don't know where these numbers are coming from.

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0hey.... sin(pi/12pi) =sin pi/12*cos pi  sin pi * cos pi/2 =.25882(1) 0 =.25882

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0using Trignometry identity.... sin(ab)=sinacosb  cosasinb

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0This should help....

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0and above you are wondering how did .25882 come, its the value of sin(pi/12)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Ok, ya I'll get back to it later I have class soon. Thanks guys! :)

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0now how did I bring sin(pi/12) value....

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0okay... will wait.....

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Really I have to go but I'll be back on in 23 hours.

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0@arindameducationusc  you have a correct answer using the calculator but she wants an exact answer derived form known values like pi/6 = 1/2 and a trig identity. I got the wrong identity.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Remember your formulas. \(\sin(\alpha + \beta) = \sin(\alpha)\cdot \cos(\beta) + \cos(\alpha)\cdot \sin(\beta)\)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0So let's say... \(\dfrac{11\pi}{12} = \dfrac{2\pi}{3}\dfrac{\pi}{4}\) Can you go from there?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0It's all a little plug and chug from there.

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0yes thats a good way to do it

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0another way would be to use the identity sin^2 (11p/12) = [ 1  cos (11pi/6) ]/ 2

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0Oh that's another way, didn't think of that one too quickly.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0You have a good day @welshfella , See ya around :)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0yea theres so many trig identities  I used to know them all when i was younger Memories a bit hazy now!!1

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0@welshfella sin15 can be derived easily....

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0Sin(4530)... Using identity @welshfella I would have written it but she went offline

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0thats another way too

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.0@welshfella Thumbs up :)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0u should close this now lol @clairvoyant1
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