1.100的二次方-99的二次方+98的二次方-97的二次方+.+4的二次方-3的二次方+2的二次方-1=
(100＋99)(100-99)+...+(4+3)(4-3)+(2+1)(2-1)
=100+99+.+4+3+2+1
=5050
2.(2+1)(2^2+1)(2^4+1)(2^8+1)
=(2-1)(2+1)(2^2+1)(2^4+1)(2^8+1)
=(2^2-1)(2^2+1)(2^4+1)(2^8+1)
=...
=2^16-1