3(1-2у)(1+2у+4у^2)+(6у^3-1)=?

Question

3(1-2у)(1+2у+4у^2)+(6у^3-1)=?

Answer 1

3(1-2у)(1+2у+4у³)+(6у³-1)=3·(1-8y³)+6y³-1=3-24y³+6y³-1=2-18y³=
=2·(1-9y³)