Question

(a-1)3+3a2-3a Kak sokratit"!? Srochno!

Answer 1

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