Question

Determine whether or not each of the following signals is periodic. If the signal isperiodic, determine its fundamental period.
a. x(t)=[cos(9πt+1)]2
b. x(t)-2e-sin(10πt)
c. x(t)=e
d. x[n]-cos( 국 )
e. x(t)=cos(5t+2)+cos(9t-2)