1.原式=(8mn+m^2+16n^2)(8mn-m^2-16n^2)=-(m+4n)^2*(m-4n)^2
2.原式=x^2(x-1)+(x-1)=(x^2+1)(x-1)
3.原式=(3-1)×(3+1)×(3^2+1)×(3^4+1)…×(3^2n+1)÷2=(3^4n-1)÷2
4.原式=(1+…+x^20505)(1+x+x^2+x^3+x^4)=0
1.原式=(8mn+m^2+16n^2)(8mn-m^2-16n^2)=-(m+4n)^2*(m-4n)^2
2.原式=x^2(x-1)+(x-1)=(x^2+1)(x-1)
3.原式=(3-1)×(3+1)×(3^2+1)×(3^4+1)…×(3^2n+1)÷2=(3^4n-1)÷2
4.原式=(1+…+x^20505)(1+x+x^2+x^3+x^4)=0