Example 48

$\;\;\;(5u - 11v)^2$

$=(A - B)^2 \text{, where } A = 5u \text{ and } B = 11v $

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

$=(5u)^2 - 2(5u)(11v) + (11v)^2 $

$=25u^{2} - 110uv +121v^{2} $