Some thirty or so years ago, Bessel functions were included in the syllabus, but in our day they are out of the question. lolwut? Maybe it's just a physics

Some thirty or so years ago, Bessel functions were included in the syllabus, but in our day they are out of the question. lolwut? Maybe it's just a physics thing, but most of the differential equations we solved in college needed Bessel functions of some sort (usually because of cylindrical/spherical symmetry).