() Given the following function, find the x-value of the critical point. Determine if the function is increasing or decreasing on the given intervals, and deduce what that means for the critical point. (a) The z-value of the critical point is at c = (b) The function f(x) is: ? and ? on (-00, c), on (c, o), so the critical point thus give ? a minimum a maximum f(x) = x+6x+4.