(a^4+b^4)(a^2+b^2)-(a^3+b^3)^2=a^6+a^4b^2+a^2b^4+b^6-a^6-2a^3b^3-b^6=a^4b^2+a^2b^4-2a^3b^3=a^2b^2(a^2-2ab+b^2)=a^2b^2(a-b)^2所以若a=0或b=0或a=b所以a^2b^2(a-b)^2=0则(a^4+b^4)(a^2+b^2)=(a^3+b^3)^2若a≠0...