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