1)、（2+1）（2^2+1)(2^4+1)(2^8+1)-2^16
=(2-1)(2+1)2^2+1)(2^4+1)(2^8+1)-2^16
=2^16-1-2^16
=-1
2)a^3c-4a^2bc+4ab^2c
=AC(A^2-4AB+4B^2)=AC(A-2B)^2