4x7 x+7 (1 point) Let f(x) = f. . Find the open intervals on which f is concave up (down). Then determine the x-coordinates of all inflection points of 1. f is concave up on the intervals none 2. f is concave down on the intervals (0,1) 3. The inflection points occur at x = none 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". In the last one, your answer should be a comma separated list of x values or the word \"none". (1 point) Let f(x) = 4 12x + x3. Find (a) the intervals on which f is increasing, (b) the intervals on which f is decreasing, (c) the open intervals on which f is concave up, (d) the open intervals on which f is concave down, and (e) the x-coordinates of all inflection points. (a) f is increasing on the interva|(s) (b) f is decreasing on the interva|(s) (c) f is concave up on the open interval(s) (d) f is concave down on the open interva|(s) (e) the x coordinate(s) of the points of inflection are Notes: In the first four boxes, 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". In the last box, your answer should be a comma separated list of x values or the word "none"