Goncharenko, Andriy Viktorovich2019-03-012019-03-012019-03-01http://er.nau.edu.ua/handle/NAU/37946Such functions in mathematics are called functions of point, and in thermodynamics – functions of state. The functions by Pfaff of the second kind are called functions of line in mathematics, and in thermodynamics – functions of process.Application of calculus to thermodynamics. In mathematics they are functions by Pfaff of two variable values.enaircraftenginepiston type enginegas turbine enginethermodynamic cyclethermodynamic processPreprint