x/1*3+x/3*5+...+x/2009*2011=2010
1/2×(1-1/3+1/3-1/5+..+1/2009-1/2011)x=2010
1/2×(1-1/2011)x=2010
1/2×2010/2011x=2010
2010/4022x=2010
x=4022确定吗绝对正确