Question

a^99+a^98+2^97+2^96+2^95+……+2+1

Answer 1

设A=a^99+a^98+2^97+2^96+2^95+……+2+1

则2A=a^100+a^99+a^98+2^97+2^96+2^95+……+2

下式-上式

A=a^100-1

a^99+a^98+2^97+2^96+2^95+……+2+1=a^100-1