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anonymous
 one year ago
Find an exact value.
cos 15°
anonymous
 one year ago
Find an exact value. cos 15°

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arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.1cos(4530) using cos(AB)=cosAcosB+sinAsinB

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0cos (45  30) = cos45cos30 + sin45sin30 ?

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.1Can you solve now?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so then would it be cos (4530) = (radical) 2 / 2 * (radical) 3 / 2 + (radical) 2 / 2 * 1 / 2 ?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0would it be \[\sqrt{6} + \sqrt{2} / 4\]

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.1It should be Sqrt[3]  1/2 Sqrt[2]

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.11/sqrt(2)*sqrt(3)/2  1/sqrt(2)*1/2

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.1=sqrt(3)1 / 2sqrt(2)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0thats not one of my answer choices :(

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0these are my answer choices

arindameducationusc
 one year ago
Best ResponseYou've already chosen the best response.1okay let me see....

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@lxoser cos(15) To find this value, all you have to do is express 15 as a sum or difference of two known unit circle values. Then, take advantage of the sum/difference identities. cos(a + b) = cos(a)cos(b)  sin(a)sin(b) cos(a  b) = cos(a)cos(b) + sin(a)sin(b) [note: watch how the addition one uses subtraction, and subtraction uses addition] For this case, 15 = 45  30. Therefore, cos(15) = cos(45  30) And we know what the sine and cosine of 45 degrees and 30 degrees are. Using the cosine difference identity, we get cos(45)cos(30) + sin(45)sin(30) Which we know how to solve. (sqrt(2)/2) (sqrt(3)/2) + (sqrt(2)/2) (1/2) Keep simplifying, [ sqrt(6)/4 ] + [ sqrt(2) / 4 ] [sqrt(6) + sqrt(2)] / 4

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0so i got it right the first time, thank you so much guys for your time & help! i understand now :)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i completely agree!! lol

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0i like how if you miss one you get an 80 on the homework

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yeah i know! like really?

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0and it brings your grade down like 23 points but if you get a 100 it brings it up like .25

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0lmao omg i feel your pain so much

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0what math are you in

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0what math are you in

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0im in precal honors

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0if you go to google and type in flvs it got a 2.5 on google but flvs only shows the good ones on the side XD

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0lol, really?? florida students got it rough lol
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