1/(1-x)+1/(1+x)+2/(1+x^2)+4/(1+x^4)+(-8)/(1-x^8)=

问题描述:

1/(1-x)+1/(1+x)+2/(1+x^2)+4/(1+x^4)+(-8)/(1-x^8)=

原始=2/(1-x^2)+2/(1+x^2)+4/(1+x^4)-8/(1-x^8)
=4/(1-x^4)+4/(1+x^4)-8/(1-x^8)
=8/(1-x^8)-8/(1-x^8)
=0