Complete the identity. (cos 4x-cos 8x)/(cos 4x+ cos 8x)

Elianna Lawrence 2022-07-27 Answered
Complete the identity. cos 4 x cos 8 x cos 4 x + cos 8 x
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Answers (1)

Brenton Gay
Answered 2022-07-28 Author has 13 answers
Complete the identity. cos 4 x cos 8 x cos 4 x + cos 8 x
cos p + cos q = 2 cos 1 2 ( p + q ) cos 1 2 ( p q )
cos p cos q = 2 sin 1 2 ( p + q ) sin 1 2 ( p q )
sin ( x ) = sin x
cos ( x ) = cos x
cos 4 x cos 8 x cos 4 x + cos 8 x = 2 sin 1 2 ( 4 x + 8 x ) sin 1 2 ( 4 x 8 x ) 2 cos 1 2 ( 4 x + 8 x ) cos 1 2 ( 4 x 8 x ) = sin 6 x sin 2 x cos 6 x cos 2 x = tan 6 x tan 2 x
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