急急急 简便计算(1-1⼀2)×(1+1⼀3)×(1-1⼀4)×(1+1⼀5)×......×(1

急急急 简便计算(1-1/2)×(1+1/3)×(1-1/4)×(1+1/5)×......×(1-1/1998)
2025-02-28 04:24:03
推荐回答(1个)
回答1:

(1-1/2)*(1+1/3)*(1-1/4)*(1+1/5)*......*(1-1/1998)
=1/2*4/3*3/4*6/5*5/6*……*1998/1997*1997/1998
=1/2