SOLUTION: the number of solutions in (0,2pi) satisfying the equation cos(2x)=1 is

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Question 985115: the number of solutions in (0,2pi) satisfying the equation cos(2x)=1 is
Answer by ikleyn(52879) About Me  (Show Source):
You can put this solution on YOUR website!

If  cos%282x%29 = 1,  then  2x = 0 or 2x = 2pi.

The first equation  2x = 0  implies that  x = 0.

The second equation  2x = 2pi  implies x = 2pi%2F2 = pi.

So,  you have two potentially fitted solutions:  0  and  pi.

I don't know if you include the zero to your interval.

Usually,  when the zero is included into the interval  (0, 2pi),  then it is denoted as  [0%2C, 2pi)  and is called as semi-segment.