Example 21

$\;\;\;(6a^{6} + b^{4})^2$

$=(A + B)^2 \text{, where } A = 6a^{6} \text{ and } B = b^{4} $

$=A^2 + 2AB + B^2$

$=(6a^{6})^2 + 2(6a^{6})(b^{4}) + (b^{4})^2 $

$=36a^{12} + 12a^{6}b^{4} +b^{8} $