Determine all solutions of the given equation. Express your answer(s) using radian measure.

2 tan²x+sec² x - 2 = 0

a. x= 1/3 + k, where k is any integer
b. x= n/6+ nk, where k is any integer
c. x = 2n/3 + nk, where k is any integer
d. x = 5/6 + mk, where k is any integer
e. none of these