x/(1×3)+x/(3×5)+……+x/(2005×2007)=1003x[1/(1×3)+1/(3×5)+.+1/(2005×2007)]=1003x=1003÷[1/(1×3)+1/(3×5)+.+1/(2005×2007)]x=1003÷[1/2*(1-1/3+1/3-1/5+1/5-.+1/2005-1/2007)]x=1003÷[1/2*(1-1/2007)...
