Question

for the function (x+1)/(x^(2)-1)
(a) Determine all candidates c 2 D for inflection points, i.e. those c E D for which f''(c) does not exists or for which f''(c) = 0.
(b) On which intervals is f increasing and on which ones is it decreasing?
(c) On which intervals is f concave up and on which ones is it concave down?