Given that \ \
\
\ \
If p/q is a rational zero, then p is a factor of 4 and q is a factor of 2. \ \
\The possible values of p are ± 1, ± 2, ± 4
\The possible values for q are ± 1 , ± 2
\By the Rational Roots Theorem, the only possible rational roots are, p/q = ± 1, ± 2, ±4
\Make a table for the synthetic division and test possible real zeros.
\| \
p/q \ | \
\
2 \ | \
-6 | \5 | \ \
4 \ | \
| 1 | \ \
2 \ | \
-4 | \1 | \ \
5 \ | \
| 2 | \2 | \-2 | \1 | \6 | \
| 4 | \ \
2 \ | \
2 | \13 | \ \
56 \ | \
| -1 | \2 | \-8 | \13 | \-9 | \
| -2 | \ \
2 \ | \
-10 | \25 | \ \
-46 \ | \
| -4 | \ \
2 \ | \
-14 | \61 | \ \
-240 \ | \
Therefore there is no possible rational zero for the given polynomial function. \ \