依题意得原式=1-1/2-1/4-1/8-1/16-1/32-…-1/1024 =1/2-(1/2-1/4)-(1/4-1/8)-(1/8-1/16)-(1/16-1/32)-...(1/512-1/1024)=1/2-1/2+1/4-1/4+1/8-1/8+1/16-1/16+1/32-...-1/512+1/1024=1/1024希望能帮到你!...