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Signals and Systems Review  2.29

                      (a) Compute X(f ).
                      (b) Compute E x .
                                         dx(t)
                       (c) Compute y(t) =    .
                                          dt
                      (d) Compute Y (f ).
                        Hint: Some of the computations have an easy way and a hard way so think
                      before turning the crank!

                      Problem 2.12. The three signals seen in Figure 2.13 are going to be used to exer-
                      cise your signals and systems theory. If no functional form is given for the pulse,
                      assume ideal rectangular transitions to simplify the computations. Compute for
                      each signal




                           1
                          0.5
                        u 1 (t)  0
                         −0.5
                          −1
                             0        0.25       0.5        0.75       1
                                          Normalized Time, t/T p

                           1
                          0.5
                        u 2 (t)  0
                         −0.5

                          −1
                             0        0.25       0.5        0.75       1
                                          Normalized Time, t/T p

                           1
                         0.8
                        u 3 (t)  0.6       ut() =  2 sin  t
                                            3
                         0.4                          T p
                         0.2
                           0
                             0      0.2      0.4      0.6     0.8      1
                                          Normalized Time, t/T p
                      Figure 2.13 Pulse shapes considered for Problem 2.12.
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