Exercise 20.  Many texts give an alternative definition for  ,  starting with (5-1) as the definition for  .  

20 (a).  Use the result    and the requirement    from condition (2) to show that  

                    ,   and   ,    for all   .

Solution 20 (a).

See text and/or instructor's solution manual.

Solution.      implies   ,   

                    ,

and

                    .

This solution is complements of the authors.

(c) 2008 John H. Mathews, Russell W. Howell