Asked by Pascal

Find all solutions of the equation in the interval [0,2pi).

sec(theta)+2=0

Write your answer in radians in terms of pi
Answered by Steve
sec x = -2, so
cos x = -1/2
solutions in QII and QIII
Answered by Pascal
how do I write this in radians in radians in terms of pi
Answered by Steve
c'mon, guy.

cos π/3 = 1/2, so

cos 2π/3 = cos 4π/3 = -1/2

x = 2π/3 or 4π/3