Basic operations, simple factors, factor Theorem, Remainder Theorem, Division of polynomials.
Let f(x) = x3 - 6x2 + 11x - 6.
Then, which one of the folllowing is not a factor of f(x) ?
Since x = -3 does not make (x3 - 6x2 + 11x - 6) zero,
so (x + 3) is not a factor.