Answer :

[tex]2n(n^2+3n+4)\\\\=(2n)(n^2)+(2n)(3n)+(2n)(4)\\\\=\boxed{2n^3+6n^2+8n}[/tex]

Answer: [tex]2n^{3} + 6^{2} +8n[/tex]

Step-by-step explanation: