Let f(x) = 8x + 9. Find the open intervals on which f is increasing (decreasing). Then determine the x-coordinates of all relative maxima (minima). f is increasing on the intervals 2. f is decreasing on the intervals 3. The relative maxima of f occur at a = none 4. The relative minima of f occur at x = none 1. Notes: In the first two, your answer should either be a single interval, such as (0,1), a comma separated list of intervals, such as (-inf, 2), (3,4), or the word "none".