(-1-1/2)*(-1-1/3)*(-1-1/4)*(-1-1/5)*(-1-1/6)*……*(-1-1/9)*(-1

(-1-1/2)*(-1-1/3)*(-1-1/4)*(-1-1/5)*(-1-1/6)*……*(-1-1/9)*(-1 计算题1-1/2-1/3+1/4+1/5-1/6-1/7+1/8+1/9……-1/2006-1/2007+1/2008+ （1+1/1*3)(1+1/2*4)(1+1/3*5)……(1+1/9*11)找规律 （1-2/1)(3/1-1)(1-4/1)(5/1-1)(1-6/1)……(1-2010/1)(2011/1-1) 数列2/1+3/1+4/1+5/1+6/1+7/1+8/1+9/1+10/1+11/1……100/1求和 1-1/2+1/3-1/4+1/5-1/6+1/7-1/8+1/9……+1/19-1/20=? 1,-1/2,1/3,-1/4,1/5,-1/6,…… 1-1/2+1/3-1/4+1/5-1/6…+1/99-1/100）/（1/51+1/52+1/53+…+1/99+1/ (1-1/2)*(1-1/3)*(1-1/4)*(1-1/5)*(1-1/6)*…*（1-1/19）*（1-1/20）= (1+1/1×3) (1+1/2×4)(1+1/3×5)…(1+1/9×11) | 1/3 - 1/2 | + | 1/4 - 1/3 | + | 1/5 - 1/4 | …… + | 1/2009 1/2×4+1/3×5+1/4×6+1/5×7+……+1/8×10+1/9×11