Question

Упростите выражение
a^3-(a+1)^3+3a^2

Answer 1

$a^3-(a+1)^3+3a^2=(a-(a+1))(a^2+a(a+1)+(a+1)^2)+3a^2=\=-(3a^2+3a+1)+3a^2=-3a-1$