Question

Giúp với ạ ,em đang cần gấp

Answer 1

c: Ta có: \(\left(1+2a\right)\left(1-2a\right)-a\left(a+2\right)\left(a-2\right)\)

\(=1-4a^2-a^3+4a\)

\(=-\left(a^3+4a^2-4a-1\right)\)

\(=-\left[\left(a-1\right)\left(a^2+a+1\right)+4a\left(a-1\right)\right]\)

\(=-\left(a-1\right)\left(a^2+5a+1\right)\)