Exercise 7.  Let    and  .  Show that
the equation    does not hold for these specific choice of  .  

Solution 7.

See text and/or instructor's solution manual.

Calculation reveals that

        ,  
and
        .

Since ,  we have    for this "counter example."

This solution is complements of the authors.

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