(a) list the possible rational zeros of f,
(b) use a graphing utility to graph f so that some of the possible zeros in part (a) can be disregarded, and then
(c) determine all real zeros of f.
1. f (x) = −2x4 + 13x3 − 21x2 + 2x + 8
2. f (x) = 4x4 − 17x2 + 4