Example 66

$\;\;\;(11 - 2kl^{2})^2$

$=(A - B)^2 \text{, where } A = 11 \text{ and } B = 2kl^{2} $

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

$=(11)^2 - 2(11)(2kl^{2}) + (2kl^{2})^2 $

$=121 - 44kl^{2} +4k^{2}l^{4} $