5/9-5/11+4/9-8/11=(5/9+4/9)-(5/11+8/11)=1-13/11=-2/11
5/9-5/11+4/9-8/11=(5/9+4/9)-(5/11+8/11)=1-13/11=-2/11祝你好运
5/9-5/11+4/9-8/11=(5/9+4/9)-(5/11+8/11)=9/9-13/11=1-(1+2/11)=-2/11