Answer:
sec(154.158°) = -1.1111
Step-by-step explanation:
given data
cos(theta°) = −0.9
to find out
sec(theta°)
solution
as we know that given equation
cos(theta°) = −0.9
theta° = [tex]cos^{-1} (-0.9)[/tex]
theta° = 154.158 .................1
so now we find
sec(theta°)
and we know
sec(theta°) = [tex]\frac{1}{cos (theta)}[/tex] .................2
sec(theta°) = [tex]\frac{1}{cos (154.158)}[/tex] ..............3
sec(theta°) = [tex]\frac{1}{(-0.9)}[/tex]
sec(154.158°) = -1.1111