[tex]2n(2n+2)(2n+4)=8(2n+4)\\2n(4n^2+8n+4n+8)=16n+32\\8n^3+16n^2+8n^2+16n-16n-32=0\\8n^3+24n^2-32=0\\n^3+3n^2-4=0\\n^3-n^2+4n^2-4=0\\n^2(n-1)+4(n^2-1)=0\\(n-1)(n^2+4(n+1))=0\\(n-1)(n^2+4n+4)=0\\(n-1)(n+2)^2=0\\n=1 \vee n=-2[/tex]
-2 odpada, bo mają być liczby naturalne
[tex]2n=2\cdot1=2\\2n+2=2+2=4\\2n+4=2+4=6[/tex]
Te liczby to 2,4,6.