Answer
$(x^3+3)(2x^3+5)$.
Work Step by Step
The given expression is
$=2x^6+11x^3+15$
We can write
$=2(x^3)^2+11x^3+15$
Substitute $x^3=u$.
$=2(u)^2+11u+15$
Simplify.
$=2u^2+11u+15$
Rewrite $11u$ as $6u+5u$.
$=2u^2+6u+5u+15$
Factor.
$=2u(u+3)+5(u+3)$
$=(u+3)(2u+5)$.
Substitute back $u=x^3$.
$=(x^3+3)(2x^3+5)$.
