b) for the values of k and p found in part a on what intervals in f' positive

C)give a graphical interpretation for the graph of f for those values of x for which f' is popositives

i got k to equal -2 and p to equal 2

but I don't know how to tell if its positive...isn't just where it's above the x axis?...so then the graph of f' would look like an absolute value function with vertex at 1 and the graph where f' is positive would be the same graph because it does not cross the x axis into the third and forth quad