(1 point) Letf(x) =-x4-8x3 + 4x-8 Find the open intervals on which f is concave up (down). Then determine the x-coordinates of all inflection points of f 1. f is concave up on the intervals 2. f is concave down on the intervals 3. The inflection points occur at x = 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".
ff is concave up on the intervals------------------
2.
ff is concave down on the intervals---------------
3.
The inflection points occur at xx =----------------
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 xx values or the word "none".