Reconsider Exercise 11.2.6 if Q(x, t) = g(x)eit. *(a) Solve for u(x, t). Show that the influence function for g(x) is an outwardpropagating wave. (b) Instead, determine a particular solution of the form u(x, t) = (x)eit. (See Exercise 8.3.13.) (c) Compare parts (a) and (b).

CHAPTER 2.3- CARTESIAN PRODUCTS OF SETS The Cartesian product of A and B is A x B o A x B= {(a,b): a € A and b € B} o (a,b) is an ordered pair Example: A = {1,2} B= {x,y} A X B= {(1,x), (1,y), (2,x), (2,y) The cardinality is 4 If |A| =m and |B| = n then |AxB|= m*n o Options of A multiplied by options of B give us the cardinality...