the linear equation can be represented as a linear transformation of the phase plane. Since a segment on the phase plane under a non-degenerate linear transformation goes into a segment, it can be characterized by a single point. Therefore, we choose the extreme point $ r = a $, which will characterize the extreme trajectory:</p>
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\[\gamma m\ddot r =\displaystyle\frac {2 I e} {\gamma ^ 2 a\upsilon}.\]</div>
<p>We proceed to differentiation with respect to $ z $, tak