Number of solutions of the equation tan x + sec x = 2 cos x, lying in the interval [0, 2p] is

tan x + sec x = 2cosx
sin x + 1 = 2cos²x
sin x + 1 = 2 (1 - sin²x)
2 sin²x + sin x - 1 = 0
Hence, we get
sin x = - 1, or sin x = 1/2
sin x = -1 orcosx = 0, which is not possible
? sin x = 1/2
x = p or x = p - (p / 6), in the interval [0, 2p]
x = p or x = 5p / 6
Thanks