2022 AMC 12A Problems/Problem 21
Solution
is equal to
by difference of powers.
Therefore, the answer is a polynomial that divides
but not
.
Note that any polynomial
divides
if and only if
is a factor of
.
The prime factorizations of
and
are
and
, respectively.
Hence,
is a divisor of
but not
.
By difference of powers,
.
Therefore, the answer is E.