1-1/2)+(1/2-1/3)+(1/3-1/4).(1/2009-1/2010) = 1-1/2+1/2-1/3+1
2个回答
你写的这一步是去括号
然后-1/2+1/2抵消
-1/3+1/3抵消
……
-1/2009+1/2009抵消
所以=1-1/2010=2009/2010
相关问题
(-1*1/2)+(-2*1/3)+(-3/1*1/4)+...+(-1/2009*2010)+(-1/2010*1/2
1/1*2+1/2*3+1/3*4+.1/2009*2010=?
1/1*2+1/2*3+1/3*4+…+1/2009*2010
(1/2+1/3+1/4+...+1/2010)(1+1/2+1/3+...+1/2009)-(1+1/2+1/3+..
|1/2-1|+|1/3-1/2|+1/4-1/3|+...|1/2009-1/2008|+|1/2010-1/2009
计算:|2/1-1|+|3/1-2/1|+|4/1-3/1|.+|2010/1-2009/1|?
|1/3-1/2|+|1/4-1/3|+...+|1/2010-1/2009|
1.-|-3|= 2.+|-3|= 3.-|+3|= 4.|1/2011-1/2010|+|1/2010-1/2009|
1/1*2+1/2*3.1/2009*2010.1/1*3+1/3*5...1/2009*2011
化简:|1/2-1|+|1/3-1/2|+|1/4-1/3|+……+|1/2010-1/2009|