The easiest way to calculate this function value is to use reciprocal trigonometric identities
[tex]\sec x=\frac{1}{\cos x}[/tex]We already know the value of cos 0, which is 1, replace this value in the equation
[tex]\begin{gathered} \sec 0=\frac{1}{\cos 0} \\ \sec 0=\frac{1}{1} \\ \sec 0=1 \end{gathered}[/tex]It means sec 0 is 1
