Solution
= Solution
\b[No.] The <center of a group> satisfies
$$
Z(C_2\times D_8)
=C_2\times Z(D_8)
\cong C_2\times C_2,
$$
because $Z(D_8)=\{1,r^2\}\cong C_2$. This centre is not <cyclic group>[cyclic]. The <cyclic-center obstruction to a faithful irreducible representation> therefore rules out a faithful irreducible complex representation of $C_2\times D_8$.