Question

  giải giúp vs ạ

Answer 1

a: \(-3x\left(x^2-2x-1\right)\)

\(=-3x\cdot x^2+3x\cdot2x+3x\cdot1\)

\(=-3x^3+6x^2+3x\)

b: \(x^2\left(-2x+1-x^2\right)\)

\(=-x^2\cdot2x+x^2\cdot1-x^2\cdot x^2\)

\(=-2x^3+x^2-x^4\)