Help me find all the solutions in the interval [0, 2pi) : cos x - 1 = 0.?

Question

a. (pi/4) , (7pi/4)
b. (pi/2) , (3pi/2)
c. 0
d. pi
e. none of these

Answer 1

cos x - 1 = 0
cos x = 1
for x in the interval [0,2pi)
x = 0
(answer c)