SEC function
Secant function. SEC(x) returns the secant of x. The argument x must be expressed in radians. To convert degrees to radians you use the RADIANS function. The function is undefined when x = /2 + for any integer (i.e. when cos(x) = 0).
The secant is the reciprocal of the cosine:
$$ \operatorname{sec}(x) = \frac{1}{\operatorname{cos}(x)} $$
The argument x can be a real number or a matrix. When it is a matrix, the function returns a matrix with the same dimensions and with the SEC function applied to all elements.
Examples
SEC(0) equals 1
SEC(PI()/3) equals 2
SEC(RADIANS(60)) equals 2
Calculator
Graph
