1-1/2^2)*(1-1/3^2)*(1-1/4^2)*...*(1-1/2004^2)
(1-1/2-1/3-1/4-……-1/2003)(1/2+1/3+1/4+...+1/2004)-(1-1/2-1/3
(1-1/2004)+(2-1/2004*2)+(3-1/2004*3)+.+(2004-1/2004*2004)
化简(1/2+1/3+...1/2003)*(1+1/2+...1/2004)-(1+1/2+...1/2004)*(1
(1/2+1/3+.+1/2004)乘(1+1/2+.+1/2003)减(1+1/2+.1/2004)乘(1/2+1/3
1/1*2+1/2*3+1/3*4+.+1/2004*2005+1/2005*2006
(1-1/2-1/3-1/4..-1/2004)*(1+1/2+1/3+1/4+...+1/2005)-(1-1/2-1
2004*(1-2分之1)*(1-3分之1)*(1-3分之1)*(1-4分之1)*.*(1-2004分之1)
(1-1/2)(1/3-1)(1-1/4)(1/5-1)……(1/2003-1)(1-1/2004)
(1) 1,1/3,1/5,1/7,1/9 (2)- 1/2*1,1/2*2,- 1/2*3,1/2*4,-1/2*5
计算:(1/2006-1)(1/2005-1)(1/2004)… (1/3-1)(1/2-1).
1*2/1+2*3/1+3*4/1+.+2004*2005/1=
1/2*1+1/2*3+1/3*4+.+1/2004*2005=?