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The  equation  (6.38)  is  nonlinear,  so  its  integration  even  in
           simple cases of beam load is quite a challenge.

           6.9 Method of initial parameters

             The  problem  of  integration  of  the  approximate  differential
           equation of beam curved axis can be easily solved if its right side
           is a continuous function. If this condition is not met, then a single
           equation should be set up for each site of the beam and determine
           the constants of integration, which number is twice the number of
           sections of the beam. The problem may be quite cumbersome. It
           would be very convenient to have one analytical entry for bending
           moment along the length of the beam. To do this, use a supporting
           function, called the Heaviside’s unit function:
                                          0, if x   ; a
                                      x  
                                  a
                                          1, if x   . a


















                                            Figure 6.18

             Consider a console beam (fig. 6.18). The origin of coordinates
           will always be placed at the left end of the beam. When writing the
           equation  of  bending  moments  to  preserve  the  same  structure  of

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