The sound wave of two music notes can be represented by the function y = -2cos2x and y = cos2x, where x represents the time since the note is played. At what times will the frequencies of the sound waves be the same in the interval [0°, 360°)?

A.
x = 0º, 180º, 270º, 300º

B.
x = 60º, 120º, 240º, 300º

C.
x = 0º, 60º, 120º, 180º

D.
x = 60º, 100º, 140º, 180º

Question

The sound wave of two music notes can be represented by the function y = -2cos2x and y = cos2x, where x represents the time since the note is played. At what times will the frequencies of the sound waves be the same in the interval [0°, 360°)?

A.
x = 0º, 180º, 270º, 300º

B.
x = 60º, 120º, 240º, 300º

C.
x = 0º, 60º, 120º, 180º

D.
x = 60º, 100º, 140º, 180º

surjithayer · Answer

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