SOLUTION: Find the solutions of the equation that are in the interval [0, 2π). (Enter your answers as a comma-separated list. If there is no solution, enter NO SOLUTION.)
cos 2u −
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cos 2u −
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Question 963379: Find the solutions of the equation that are in the interval [0, 2π). (Enter your answers as a comma-separated list. If there is no solution, enter NO SOLUTION.)
cos 2u − cos u = 0 Answer by lwsshak3(11628) (Show Source):
You can put this solution on YOUR website! Find the solutions of the equation that are in the interval [0, 2π). (Enter your answers as a comma-separated list. If there is no solution, enter NO SOLUTION.)
cos 2u − cos u = 0
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cos 2u − cos u = 0
cos^2(u)-sin^2(u)-cosu=0
cos^2(u)-1+cos^2(u)-cosu=0
2cos^2(u)-cosu-1=0
(2cosu+1)(cosu-1)=0
..
2cosu+1=0
cosu=-1/2
u=π/3, 5π/3
or
cosu-1=0
cosu=1
u=0
(