SOLUTION: I would like some help with the following two problems if possible. I will be eternally grateful for the help provided. Thanks again.
A)find sin 7π /12
B) use π /12=(
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-> SOLUTION: I would like some help with the following two problems if possible. I will be eternally grateful for the help provided. Thanks again.
A)find sin 7π /12
B) use π /12=(
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Question 333615: I would like some help with the following two problems if possible. I will be eternally grateful for the help provided. Thanks again.
A)find sin 7π /12
B) use π /12=(π /3)-(π /4) to find cos π /12 Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! A)find sin 7π /12
sin[(7/12)pi] = sin[(5/12)pi] = sin[(pi/6)+(pi/4)]
= sin(pi/6)cos(pi/4)+cos(pi/6)sin(pi/4)]
= (1/2)(sqrt(2)/2)+(sqrt(3)/2)(sqrt(2)/2)
= [sqrt(2)/4 + sqrt(6)/4]
= [sqrt(2)+sqrt(6)]/4
= 0.9659
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B) use π /12=(π /3)-(π /4) to find cos π /12
cos(pi/12) = cos[(pi/3)-(pi/4)]
= cos(pi/3)cos(pi/4)+sin(pi/3)sin(pi/4)
= (1/2)(sqrt(2)/2) + (sqrt(3)/2)(sqrt(2)/2)
= [sqrt(2)/4] + [sqrt(6)/4]
= [sqrt(2)+sqrt(6)]/4
= 0.9659
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Cheers,
Stan H.
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