Answer:
3x^4-18x^3+27x^2-12x
Step-by-step explanation:
Multiply the second paréntesis for each term of the first parentage
3x^2×(x^2-2x+1)-12x×(x^2-2x+1)
Multiply parentage by 3x^2
3x^4-6x^3+3x^2-12x×(x^2-2x+1)
Multiply the parentage by -12x
3x^4-6x^3+3x^2-12x^3+24x^2-12x
Group similar terms
3x^4-18x^3+27x^2-12x
