因为(a+b)(a-b)=a²-b²(a²-b²)(a²+b²)=a^4-b^4(a^4+b^4)(a^4-b^4)=a^8-b^8所以[1/(a-b)]+[1/(a+b)]+[2a/(a^2+b^2)]+[4a^3/(a^4+b^4)] =[2a/(a^2-b^2)]+[2a/(a^2+b^2)]+[4a^3/(a^4+b^4)...