SOLUTION: Use an Addition or Subtraction Formula to find the exact value of the expression Sin(165)

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Question 738988: Use an Addition or Subtraction Formula to find the exact value of the expression
Sin(165)
Answer by lwsshak3(11628) About Me  (Show Source):
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Use an Addition or Subtraction Formula to find the exact value of the expression
Sin(165)
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sin(165)=sin(135+30)
=(sin(135)cos(30))+(cos(135)sin(30))
=(√2/2*√3/2)+(-√2/2*1/2)
=√6/4-√2/4
=(√6-√2)/4
calculator check:
sin(165)≈0.2588..
(√6-√2)/4≈0.2588..