1.
(2x+9y^{3})(2x-9y^{3})
2.
(4x^{2}+y)(4x^{2}-y)
3.
(xy+3z^{2})(xy-3z^{2})
4.
(4x^{2}+9y^{2})(2x+3y)(2x-3y)
5.
(x^{4}+y)(x^{4}-y)
6.
(2x+y)(4x^{2}-2xy+y^{2})(2x-y)(4x^{2}+2xy+y^{2})
7.
(w^{2}+z)(w^{2}-z)
8.
(x^{2}+y^{2})(x+y)(x-y)
9.
(4x^{2}+5y^{4})(4x^{2}-5y^{4})
10.
(6x^{2}+7y^{3})(6x^{2}-7y^{3})
