You don't need to!
As the docs say, "Maxima loads the package automatically if one of the functions
eigenvectors is invoked." so try the following in your question variables.
M:matrix ([1, 2, 3], [9, 18, 30], [12, 48, 60]); V:eigenvalues(M); G:gramschmidt(x);
Thanks you. It's a neat trick. Nevertheless, why not add module loading so as not to use irrational tricks. Can I add the load command to the maximalocal.mac file ?