Understand inverse secant cosecant and cotangent functions

Question

Evaluate the following expression.

arcsec(1)

Answer 1

Answer 2

arcsec(1) or sec^-1(1) asks the question, "what angle has a secant of 1"

sec = 1/cos, so this is equivalent to the angle with a cos of 1. This occurs at 0°. Inverse secant, like inverse cosine, has a limited range of 0 to π in order to be a single-valued function