Given cos(x) the Chebyshev polynomials offer a way of quickly finding cos(nx) (check tests for more details on this).
To install CM::Permutation, copy and paste the appropriate command in to your terminal.
cpanm
cpanm CM::Permutation
CPAN shell
perl -MCPAN -e shell install CM::Permutation
For more information on module installation, please visit the detailed CPAN module installation guide.