SOLUTION: Find the exact value of sin(pi/3 - pi/4)

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Question 69789: Find the exact value of sin(pi/3 - pi/4)
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
Use identity
sin%28u-v%29=sin%28u%29cos%28v%29-cos%28u%29sin%28v%29
Let u=pi%2F3 and v=pi%2F4
sin%28pi%2F3-pi%2F4%29=sin%28pi%2F3%29cos%28pi%2F4%29-cos%28pi%2F3%29sin%28pi%2F4%29
Using the unit circle, sin%28pi%2F4%29=cos%28pi%2F4%29=sqrt%282%29%2F2 and sin%28pi%2F3%29=sqrt%283%29%2F2, and cos%28pi%2F3%29=1%2F2

sin%28pi%2F3-pi%2F4%29=sqrt%286%29%2F4-sqrt%282%29%2F4
sin%28pi%2F3-pi%2F4%29=%28sqrt%286%29-sqrt%282%29%29%2F4