Example 73

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

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

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

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

$=16p^{4} - 8p^{2}q^{4} +q^{8} $