Difference between the Time Intervals in the Special Relativistic Theory Calculated with the Aid of an Invariance Property between the Mechanical Expressions

In the relativistic mechanics, we obtain a difference between the time scale of a one-dimensional motion having a larger velocity and the time scale of a similar motion with a lower velocity. This calculation does involve usually also the differences of parameters other than time. Basing on the invariance of a pair of the mechanical parameters, it can be shown that the difference of two scales of time can be attained independently from the differences of the other physical parameters.