Question

thực hiện phép nhân 

(a+b)(a^2-ab+b^2)[a^6-(ab)^3+b^6

 

Answer 1

\(=\left(a^3+b^3\right)\left[a^6-\left(ab\right)^3+b^6\right]\)

\(=a^9-a^6b^3+a^3b^6+a^6b^3-a^3b^6+b^9\)

\(=\left(-a^6b^3+a^6b^3\right)+\left(a^3b^6-a^3b^6\right)+a^9+b^9\)

\(=a^9+b^9\)

Answer 2

\(\left(a+b\right)\left(a^2-ab+b^2\right)\left[a^6-\left(ab\right)^3+b^6\right]\)

\(=\left(a^3+b^3\right)\left(a^6-a^3b^3+b^6\right)\)

\(=a^9+b^9\)