[tex]\begin{gathered} \text{Given} \\ 3[(x^3-7x+1)-(x+4)] \end{gathered}[/tex][tex]\begin{gathered} 3[(x^3-7x+1)-(x+4)] \\ =3[x^3-7x+1-x-4] \\ =3[x^3-8x-3] \\ =3(x^3)+3(-8x)+3(-3) \\ =3x^3-24x-9 \\ \; \\ \text{Therefore,} \\ 3\left[\left(x^3\:-\:7\:x\:+\:1\right)\:-\:\left(x+\:4\right)\right]=3x^3-24x-9 \end{gathered}[/tex]
