Answer
$3a^3+5a^2+3a+10$
Work Step by Step
Using the Distributive Property, the given expression simplifies to
\begin{align*}
&
(a+2)(3a^2-a+5)
\\&=
[a(3a^2)+a(-a)+a(5)]+[2(3a^2)+2(-a)+2(5)]
\\&=
[3a^3-a^2+5a]+[6a^2-2a+10]
\\&=
3a^3+(-a^2+6a^2)+(5a-2a)+10
\\&=
3a^3+5a^2+3a+10
.\end{align*}
