What is the range of #sec x#?

1 Answer
Sep 26, 2014

The range of #secx# is #(-infty,-1]cup[1,infty)#.

Let us look at some details.

We know

#|cosx| le 1#

by taking the reciprocal,

#Rightarrow |secx|=1/|cosx| ge 1#

(Note that we need to switch the direction of inequality.)

Hence, its range is #(-infty,-1]cup[1,infty)#.