已知M=(2+1)(2^2+1)(2^4+1)(2^8+1) ……(2^16已知M=(2+1)(2^2+1)(2^4+1)(2^8+1)……(2^16+1)(2^128+1)

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已知M=(2+1)(2^2+1)(2^4+1)(2^8+1) ……(2^16已知M=(2+1)(2^2+1)(2^4+1)(2^8+1)……(2^16+1)(2^128+1)
已知M=(2+1)(2^2+1)(2^4+1)(2^8+1) ……(2^16
已知M=(2+1)(2^2+1)(2^4+1)(2^8+1)
……(2^16+1)(2^128+1)

已知M=(2+1)(2^2+1)(2^4+1)(2^8+1) ……(2^16已知M=(2+1)(2^2+1)(2^4+1)(2^8+1)……(2^16+1)(2^128+1)
答:补一个因数1=2-1,值不变,利用平方差公式:
M=(2+1)(2^2+1)(2^4+1)(2^8+1)(2^16+1).(2^128+1)
=(2-1)(2+1)(2^2+1)(2^4+1)(2^8+1)(2^16+1).(2^128+1)
=(2^2-1)(2^2+1)(2^4+1)(2^8+1)(2^16+1).(2^128+1)
=(2^4-1)(2^4+1)(2^8+1)(2^16+1).(2^128+1)
=(2^8-1)(2^8+1)(2^16+1).(2^128+1)
=(2^16-1)(2^16+1).(2^128+1)
=(2^32-1).(2^128+1)
=2^256-1

令m=(2+1)(2^2+1)(2^4+1)(2^8+1)……(2^128+1)
两边同时乘(2-1)得:
(2-1)m=(2-1)(2+1)(2^2+1)(2^4+1)(2^8+1)……(2^128+1)
m=(2^2-1)(2^2+1)......(2^128+1)
=......
=(2^128-1)(2^128+1)
=2^256-1
=(2^4)^64-1
=16^64-1
x=64

M=(2+1)(2^2+1)(2^4+1)(2^8+1)
……(2^64+1)(2^128+1)
=(2-1)(2+1)(2^2+1)(2^4+1)(2^8+1)
……(2^64+1)(2^128+1)
=(2^2-1)(2^2+1)(2^4+1)(2^8+1)
……(2^64+1)(2^128+1)
=(2^4-1)(2^4+1)(2^8+1)
……(2^64+1)(2^128+1)
=2^256-1

供你参考。帮助别人快乐自己!

先乘以(2-1),得到(2^2-1)(2^2+1)(2^4+1)(2^8+1)
……(2^16+1)(2^128+1),根据(x-1)(x+1)=x^2-1,可以得到2^256-1