x^4 - 8x^5 + 16x^6
(2b^3 + 2b^2)^2
(9x^2 - 2x)^2
(4a^6 - a^3)(4a^6 + a^3)
81x^4 - 36x^3 + 4x^2
9x^2 +30x + 25
(2b^3 + 2b^2)(2b^3 - 2b^2)
(4a^2 - 25a^4)
(m + 2m^3)(m - 2m^3)
(2a - 5a^2)(2a + 5a^2)
(16a^12 - a^6)
(x^2 - 81)
(m^2 - 4m^6)^2
m^4 - 8m^8 + 16m^12
(x^2 - 4x^3)^2
(4b^6 - 4b^4)
(3x+5)^2
(x+9)(x-9)
(m^2 - 4m^6)
4b^6 + 8b^5 + 4b^4