f x x 9x 21x 1 Enter DNE if an answer does not exist a Give the domain of f in interval notation intervals b Determine the intervals on which f is concave up down f is concave up on f is concave down on Based on your answers in a and b determine the inflection points of f help numbers Each answer should be entered as an ordered pair x y Separate multiple answers with commas d Find the critical numbers of f and use the Second Derivative Test when possible to determine the relative extrema Relative maxima occur at x help commas Relative minima occur at x commas e Find the x values where f x has a relative maximum or minimum f has relative maxima at x commas f has relative minima at x commas Separate multiple answers with Separate multiple answers with Separate multiple answers with Separate multiple answers with