Ask a question
0 0


Tutors, please sign in to answer this question.

2 Answers

This is not a monotonic smooth function. If f(x)=I6xI, then you have to distinguish two domains: x< 0 when
  f(x) =- 6x, and x > 0 when f(x) = 6x. 
                  Thus,   f'(x) = -6 for x<0    and f'(x) = 6 for x > 0
                  The derivative f'(x) is not a continuous function because there is no derivative at x=0 
                 (the graph of f(x) =I6xI  is broken at x = 0).


LOL:  We need to constantly remind our students to write clearly.  I don't think he meant abs(6x), but I'm not sure what "6.x" means - probably just multiplication ---->  6x