What's odd here is the line of demarcation between mathematics (or technical subjects in general) and liberal arts -- two of the quadrivium are arithmetic and geometry. And while we can probably agree that the influential aspects of astrology are no longer worth serious study (except, perhaps, from a historical, psychological or sociological perspective), the periodicity -- the astronomy -- of astrology was also considered part of a well-rounded education. (Music was the fourth element of the quadrivium.)

Perhaps it would be best to refer to a completely non-technical education as trivial since it ignores more of the liberal arts than it incorporates.