Example 68

$\;\;\;(6p^{4} - 5q^{7})^2$

$=(A - B)^2 \text{, where } A = 6p^{4} \text{ and } B = 5q^{7} $

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

$=(6p^{4})^2 - 2(6p^{4})(5q^{7}) + (5q^{7})^2 $

$=36p^{8} - 60p^{4}q^{7} +25q^{14} $