Question

Verify: $(a+b{)}^3=a^3+3a^{2}b+3a{b}^2+b^3$.

Answer 1

$(a+b{)}^3$ can be written as, $(a+b)(a+b)(a+b)$

$⟹\left[\right(a+b)\times (a+b\left)\right]\times (a+b)$

$⟹[a\times a+a\times b+b\times a+b\times b]\times (a+b)$

$⟹(a^2+ab+ab+b^2)\times (a+b)$

$⟹(a^2+2ab+b^2)\times (a+b)$

$⟹a^3+3a^{2}b+3a{b}^2+b^3$

Hence, verified.