[tex]12x^3=\boxed{2}\cdot2\cdot\boxed{3}\cdot \boxed{x}\cdot \boxed{x}\cdot x\\\\18x^2=\boxed{2}\cdot\boxed{3}\cdot3\cdot \boxed{x}\cdot \boxed{x}\\\\6x^4=\boxed{2}\cdot\boxed{3}\cdot \boxed{x}\cdot \boxed{x}\cdot x\cdot x\\\\LCF(12x^3,\ 18x^2,\ 6x^4)=\boxed{2}\cdot\boxed{3}\cdot\boxed{x}\cdot\boxed{x}=6x^2\\\\Answer:\ \boxed{\boxed{6x^2}}[/tex]
