Question

What are the possible rational zeros of f(x) = x4 + 2x3 − 3x2 − 4x + 20? (1 point)

A.) 1, 2, 4, 5, 10, 20

B.) ± 1, ± 2, ± 3, ± 4, ± 5, ± 6, ± 7, ± 8, ± 9, ± 10, ± 11, ± 12, ± 13, ± 14, ± 15, ± 16, ± 17, ±18, ± 19, ± 20

C.) ± 1, ± 2, ± 4, ± 5, ± 10, ± 20

D.) 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20

Answer 1

The possible rational zeros of polynomial function
`f(x) = x^4 + 2x^3 - 3x^2-4x + 20` could be only among the divisors of the free term of this polynomial function.

The free term is 20 and the divisors of 20 are:

`\pm 1, \pm 2, \pm 4, \pm 5, \pm 10, \pm 20.`

Answer: correct choice is C