Sum and difference formula sin, Pre clac question!!?

S

sean b

New member
?/12 = 9?/12-8?/12 = 3?/4-2?/3

sin(3?/4-2?/3) = sin(3?/4)cos(2?/3) - sin(2?/3)cos(3?/4)
=?2/2(-1/2) - (?3/2)(-?2/2)
=-?2/4 - (-?6/4)
=-?2+?6/4
=[?6-?2]/4
 
the sum and difference formula = sin(x1+x2) = sinx1cos2+cos1sin2, sun(x1-x2) = sinx1cosx2 - cosx1sinx2.

how would i use that formula on sin ?/12 ???

show would so i know how you did it thanks!!!
show work*
 
Im guessing you have to evaluate pi/12?

pi/12 isnt on the unit circle, so you have to split it up into pieces that are
so you can do 3pi/4 = 9pi/12, and -2pi/3= -8pi/12
so you get sin(3pi/4 - 2pi/3)

sincos+cossin
sin(3pi/4)cos(2pi/3) - sin(2pi/3)cos(3pi/4)
solve it! :D
 
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