Find the (4,2) Pade rational function approximation for 1/cos(x), so
that it matches a Taylor series expansion about x = 0. Note that
Maple will do it for you. For help, use ?Pade. To access the Pade
command directly, start with the command with(numapprox);.
Do a Taylor series expansion of 1/cos(x) and the Pade approximation
to check that Maple did it correctly.
Find the pole of the Pade approximation closest to x = 0,
and compare with the known location of the corresponding pole in
1/cos(x).
Make a table comparing values of 1/cos(x) with the (4,2) Pade
approximant and the 6th degree Taylor polynomial at the values
shown: