Example 111

$\;\;\;(3 + 10x^{4}y^{7})(3 - 10x^{4}y^{7})$

$=(A + B)( A - B) \text{ , where } A = 3 \text{ and } B = 10x^{4}y^{7} $

$=A^2-B^2$

$=(3)^2 - (10x^{4}y^{7})^2 $

$=9 - 100x^{8}y^{14} $