化简求值:(x+1)(x2+1)(x4+1)(x8+1)其中x=2

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化简求值:(x+1)(x2+1)(x4+1)(x8+1)其中x=2

化简求值:(x+1)(x2+1)(x4+1)(x8+1)其中x=2
化简求值:(x+1)(x2+1)(x4+1)(x8+1)其中x=2

化简求值:(x+1)(x2+1)(x4+1)(x8+1)其中x=2
:(x+1)(x^2+1)(x^4+1)(x^8+1)其中x=2 (x-1)=1
:(x-1)(x+1)(x^2+1)(x^4+1)(x^8+1)
=(x^2-1))(x^2+1)(x^4+1)(x^8+1)
=(x^4-1))(x^4+1)(x^8+1)
=(x^8-1)(x^8+1)
=x^16-1=2^16-1

前面乘以一个(x-1)
那么变成 (x^2-1)(x^2+1)(x^4+1)(x^8+1)
=(x^4-1)(x^4+1)(x^8+1)
=(x^8-1)(x^8+1)
=x^16-1

设y=(x+1)(x2+1)(x4+1)(x8+1)
当x=2时
y=(2-1)(2+1)(2^2+1)(2^3+1)(2^4+1)(2^8+1)
两边同时乘以(2-1)
(2-1)y=(2-1)(2+1)(2^2+1)(2^3+1)(2^4+1)(2^8+1)
利用平方差公式
y=2^16-1
所以(2+1)(2^2+1)(2^3+1)(2^4+1)(2^8+1)=2^16-1

2^16-1

=(2+1)(2^2+1)(2^4+1)(2^8+1)
=(2-1)(2+1)(2^2+1)(2^4+1)(2^8+1)
=2^16-1