Respuesta :

θ

=

2

π

3

+

2

π

n

,

4

π

3

+

2

π

n

, for any integer

n

[tex]~~~\sec \theta = 2\\\\\implies (\cos \theta)^{-1} = 2\\\\\implies \cos \theta =\dfrac 12\\ \\\implies \theta = 2n\pi \pm \dfrac{\pi}3[/tex]