(a+2)(a-2)(a^4+4a^2+16)=(a^2-4)(a^4+4a^2+16)=a^6-4^3=a^6-64 (x^2+2xy+y^2)(x^2-xy+y^2)^2=(x+y)^2(x^2-xy+y^2)^2=[(x+y)(x^2-xy+y^2)]^2=(x^3+y^3)^2=x^6+2x^3y^3+y^6(x+y+z)(-x+y+z)(x-y+z)(x+y-z) =[(x+y+z)(x...