(1) 1,2,3( )
(1) 1,2,3( )
由下列不等式:1>1/2,1+1/2+1/3>1,1+1/2+1/3+.+1/7>3/2,1+1/2+1/3+.+1/1
2(3+1)(3^2+1)(3^3+1)(3^4+1)(3^8+1)+1
2 1 -2 -3
(1+1/2+1/3+.+1/2010)×(1/2+1/3+.+1/2011)-(1+1/2+1/3+.+1/2011)
(1+1/2+1/3+...+1/2006)*(1/2+1/3+1/4+...1/2007)-(1+1/2+1/3+..
(1-1/2-1/3-...-1/2009)(1/2+1/3+1/4...+1/2010)-(1-1/2-1/3-...
(1/2+1/3+...+1/2014)(1+1/2+1/3...+1/2013)-(1+1/2+1/3+...+1/2
(1/2+1/3+...+1/2000)*(1+1/2+...+1/1999)-(1+1/2+...+1/2000)*(
(1-1/2)*(1-1/3)*...*(1-1/1000)
奥数六年级1/2/(1+1/2)+1/3/(1+1/2)(1+1/3)+1/4/(1+1/2)(1+1/3)(1+1/4
1 1 1 1------ + ------ + ------ + .+ -------------- =1×2 2×3