Question

Помогите пожалуйста!

Answer 1

1/(1+x^4)+2/(1+x²)+(1-x+1+x)/(1-x)(1+x)=1/(1+x^4)+2/(1+x²)+2/(1-x²)=
=4/(1+x^4)+2(1-x²+1+x²)/(1-x²)(1+x²)=4/(1+x^4)+4/(1-x^4)=
=4(1-x^4+1+x^4)/(1-x^4)(1+x^4)=8/(1-x^8)