Wiley signals and systems e book TLFe BO 519

504

Apprridis A. Sohitions to the Exercises

Solution 11.5

Solution 11.6
a,) I n grncral, t,he sum of licrioclic hiiictioiis is only pcriodic if cnch period is a
rat,ioiial proportiori of t,he otliers. The period of the sLiirirrirtl signe,l 2' is t,llrli
tlic snisllest common inultiplc of the individual periods, aiid the fuiidn.menta1
frequency of thc signal f = is t,hr largest coimnion divisor of t,hc individual
fuiiclament,al frequencies.
2, it):

x2(t)

fiindnmeiital freqiieiiry of circnit 3u?0. period
siii(dOtjcos(&wot)

=

Yi

+

=

0.5 Isirl((1 - f i ) i ~ o t ) sin((1

+ JT)q,t)]