SOLUTION: An important trigonometric identity is
cos(a + b) = cos a cos b − sin a sin b,
which is called the cosine addition formula.
Use this formula to show that cos2(a) = (1 + co
Algebra ->
Trigonometry-basics
-> SOLUTION: An important trigonometric identity is
cos(a + b) = cos a cos b − sin a sin b,
which is called the cosine addition formula.
Use this formula to show that cos2(a) = (1 + co
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Question 1082826: An important trigonometric identity is
cos(a + b) = cos a cos b − sin a sin b,
which is called the cosine addition formula.
Use this formula to show that cos2(a) = (1 + cos(2a))/2 Answer by Alan3354(69443) (Show Source):
