Page 245 - Schaum's Outline of Theory and Problems of Signals and Systems
P. 245

FOURIER ANALYSIS OF TIME SIGNALS AND SYSTEMS                  [CHAP.  5



                     Thus, the complex Fourier coefficients for cos(2t + 7r/4)  are













                 (d)  By the result from Prob. 1.14 the fundamental period  To of  x(t) is  7r  and w,, = 21r/T,  = 2.
                     Thus,





                     Again using Euler's  formula, we  have










                     Thus, the complex  Fourier coefficients for cos 4t + sin 6t  are




                     and all other c,  = 0.
                 (e)  From  Prob.  1.16(e) the fundamental  period  To of  x(t) is  rr  and  w,  = 2rr/T,,  = 2.  Thus,





                     Again  using  Euler's  formula, we get










                     Thus, the complex  Fourier coefficients for sin2 t  are

                                                  -   I
                                              Cpl  - --   c0=$     c,=-$
                                                      4
                     and all other  c,  = 0.

           5.5.  Consider the periodic square wave  x(t) shown  in  Fig. 5-8.

                 (a)  Determine the complex exponential Fourier series of  x(t ).
                 (b)  Determine the trigonometric Fourier series of  x( t 1.
   240   241   242   243   244   245   246   247   248   249   250