Step 1:
\The function is
.
Identify Rational Zeros. \ \
\Usually it is not possible to test all possible zeros of a polynomial function using only synthetic substitution.
\The Rational Zero Theorem can be used for finding the some possible zeros for higher degree polynomial.
\
If
is a rational zero, then
is a factor of 26 and
is a factor of 1.
The possible values of
are ± 1, ± 2, ± 13 and ± 26.
The possible values for
are ± 1.
So,
= ± 1, ± 2, ± 13 and ± 26.
Step 2:
\Make a table for the synthetic division and test possible zeros.
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Since
,
is a zero. The depressed polynomial is
. \ \
The depressed polynomial,
, is quadratic equation then the zeros of equation are calculated as
. \ \
Substitute
,
and
in the above expression. \ \

Therefore roots of
are
.
Step 3:
\Factor theorem,
\When
then
is a factor of polynomial.
Factors of the polynomial are
then \ \

Solution :
\The Complex zeroes of the function are
.
Factored form is
.