Правоохранительная и правозащитная деятельность: вчера, сегодня, завтра.
Российский университет дружбы народов (РУДН).
2021.
С. 85-87
The classical problem about oscillation of music strings is considered. Its solution can be represented as Fourier series, and also as elementary functions. Such a representation is valid only over the fi of real numbers and doesn't belong Liouville theory. This circumstance lids to several diffi at work with the solutions in CAS. A typical example from CAS Maple is considered.