SOLUTION: Find all solutions of the equation 2 cos x -1 = 0. The answer is A+Bkpi and C+Dkpi where k is any integer, 0<A<C<2pi. Please help.

Algebra ->  Trigonometry-basics -> SOLUTION: Find all solutions of the equation 2 cos x -1 = 0. The answer is A+Bkpi and C+Dkpi where k is any integer, 0<A<C<2pi. Please help.      Log On


   

Question 928162: Find all solutions of the equation 2 cos x -1 = 0.
The answer is A+Bkpi and C+Dkpi where k is any integer, 0 Please help.
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
2cos%28x%29-1=0
2cos%28x%29=1
cos%28x%29=1%2F2
x=pi%2F3 and x=%285%2F3%29pi
Both are 2pi-periodic.
x=pi%2F3%2B%282pi%29k
x=%285%2F3%29pi%2B%282pi%29k