Ответ:
- \(-0.2x\cdot(x^4-1.6x^3+2.3x)\cdot x^2=-0.2x^7+0.32x^6-0.46x^4\).
- \(ab(0.3a^2-1.2ab+1)a^3=0.3a^6b-1.2a^5b^2+a^4b\).
- \(-(0.5a^2b^2-ab+0.9)(-ab)=0.5a^3b^3-a^2b^2+0.9ab\).
- \(-b^3(-0.3a^2b-0.4ab+1)ab^2=0.3a^3b^6+0.4a^2b^6-ab^5\).
- \(4x^ny(3x-2y^n)=12x^{n+1}y-8x^ny^{n+1}\).
