Question

How do you evaluate
lim x -> inf inverse sec(x/2)

Answer 1

As x gets large, you're looking for the angle whose secant is x/2, or whose cosine is 2/x (since secant = 1/cosine). As x approaches infinity, this is the angle whose cosine is 2/infinity, or 0, and that angle is Pi/2.

Answer 2

Oh that makes sense, thank you