what is the volume

Question

Using disks or washers, find the volume of the solid obtained by rotating the region bounded by the curves y=sec(x), y=1, x=-1 and x=1 about the x-axis 

Answer 1

By washer method volume v = π ∫_-1¹(sec²x - 1)dx = 2π(tanx - x)₀¹ = 2π(tan1 - 1)