Answer
$18k^4+12k^3+6k^2$
Work Step by Step
Using $a(b+c)=ab+ac$ or the Distributive Property, the product of the given expression, $
6k^2(3k^2+2k+1)
,$ is
\begin{array}{l}\require{cancel}
6k^2(3k^2)+6k^2(2k)+6k^2(1)
\\\\=
18k^4+12k^3+6k^2
.\end{array}