Question

(a+b)(a+b)(a+b)

Answer 1

\(\left(a+b\right)\left(a+b\right)\left(a+b\right)\\ =\left(a^2+ab+ab+b^2\right)\left(a+b\right)\\ =a^3+a^2b+ab^2+a^2b+ab^2+a^2b+ab^2+b^3\\ =a^3+3a^2b+3ab^2+b^3\)

Answer 2

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