(2+1)(2²+1)(2^4+1)(2^8+1);
=(2-1)(2+1)(2²+1)(2^4+1)(2^8+1);
=(2²-1)(2²+1)(2^4+1)(2^8+1);
=(2^4-1)(2^4+1)(2^8+1);
=(2^8-1)(2^8+1);
=2^16-1
(1)一变:(2+1)(2²+1)(2^4+1)…(2^2n+1);
=(2-1)(2+1)(2²+1)(2^4+1)…(2^2n+1);
=……
=(2^2n-1)…(2^2n+1);
=2^4n-1
(2)二变:2×(3+1)(2²+1)(3^4+1)…(3^2n+1).
=(3-1)(3+1)(3²+1)(3^4+1)…(3^2n+1);
=……
=(3^2n-1)…(3^2n+1);
=3^4n-1
(2+1)(2²+1)(2^4+1)(2^8+1);
=(2+1)×(2-1)×(2²+1)(2^4+1)(2^8+1)除(2-1)
=(2²-1)(2²+1)(2^4+1)(2^8+1)除1
=(2^4-1)(2^4+1)(2^8+1)
=(2^8-1)(2^8+1)
=2^16-1
平方差就可以了
、、、
你没