SOLUTION: Find all EXACT solutions of the equation
cos(x ) = −1/2
in the interval [0,2π). If there is more than one answer, enter them in a list separated by commas.
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-> SOLUTION: Find all EXACT solutions of the equation
cos(x ) = −1/2
in the interval [0,2π). If there is more than one answer, enter them in a list separated by commas.
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Question 1060248: Find all EXACT solutions of the equation
cos(x ) = −1/2
in the interval [0,2π). If there is more than one answer, enter them in a list separated by commas. Answer by Edwin McCravy(20060) (Show Source):
The reference angle is the acute angle whose cosine is 1/2.
We can find it on the unit circle:
.
It is
The cosine is negative in quadrants II and III, so we find
those two angles on the unit circle as
and
Edwin
.
It is 