Hello All, This problem comes from #18 of section 4.3 out of stewarts 6th edition. The Question: Consider the following function: f(x)= e^(-x) * sqrt(x) What I am trying to find. a.) Find the intervals on which f is increasing and decreasing. b.) find any relative extrema. c.) find the intervals of concavity. d.) find all inflection points. For part a. I have taken the first derivative and got. 1/2x^-(1/2) *e^-x - e^-x * sqrt (x) after simplifying i got e^-x= 0 and 1/2 x^-1/2 - sqrt x = 0 I know i need to find these for my critical points but I am having difficulty proceeding. for extrema i know i plug in values between my critical points to see the critcal values. after that I know I take the 2nd derivative to find critical points for my concavity. thanks for your help!!