Question

Упростите выражение:
а) (a-2)(a^2+a-1)-a^2(a-1)

б) (3-p)(9+3p+p^2)-(1-p^3)

Answer 1

а) (a-2)(a^2+a-1)-a^2(a-1)
   a^3-a^2-3a+2-a^3+a2=-3a+2

б)(3-p)(9+3p+p^2)-(1-p^3)
    27+9p+3p^2-9p-3p^2-p^3-1+p^3=27-1

Answer 2

a)
$(a-2)(a^2+a-1)-a^2(a-1)=\ =a^3+a^2-a-2a^2-2a+2-a^3+a^2=\ =0cdot a^3+0cdot a^2-3a+2=2-3a$
б)
$(3-p)(9+3p+p^2)-(1-p^3)=27-p^3-1+p^3=26.$