SOLUTION: Find all solutions of the equation in the interval [0, 2π). (Enter your answers as a comma-separated list. If there is no solution, enter NO SOLUTION.)
2cos^2x+cosx−1=0
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-> SOLUTION: Find all solutions of the equation in the interval [0, 2π). (Enter your answers as a comma-separated list. If there is no solution, enter NO SOLUTION.)
2cos^2x+cosx−1=0
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Question 1114641: Find all solutions of the equation in the interval [0, 2π). (Enter your answers as a comma-separated list. If there is no solution, enter NO SOLUTION.)
2cos^2x+cosx−1=0 Answer by stanbon(75887) (Show Source):
You can put this solution on YOUR website! 2cos^2x+cosx−1=0
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Factor:
(2cos(x)-1)(cos(x)+1) = 0
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cos(x) = 1/2 or cos(x) = -1
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x = arccos(1/2) = +/-60 degrees or 180 degrees
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Cheers,
Stan H.
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