Exercise 9.  Show that   ,  where n is a positive integer.  

Solution 9.

See text and/or instructor's solution manual.

Solution.  Apply the quotient rule and get

           

We are done.   

Aside.  We can let Mathematica double check our work.

This solution is complements of the authors.

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