1/4+1/12+1/24+1/40……+1/19800=?
1/4+1/12+1/24+1/40……+1/19800=?
1/4+1/12+1/24+1/40+……+1/19800=?
4分之1+1/12+1/24+1/40…+1/19800
1/4+1/12+1/24+1/40.+1/19800
4/1+12/1+24/1+40/1+.19800/1
4/1 12/1 24/1 40/1 . 19800/1怎么算?等于多少?
如何巧算1/4+1/12+1/24+1/40+.+1/19800
1+2+3+4……+20+21+23+24……+40的简便算法
1/3+1/6=1/2 1/4+1/12=1/3 1/5+1/20=1/4 …… 1/x+
1+1=……
数学分数计算题3/4×(2.5-1/4)+5/12÷0.25原式=…………………………………………………………
200×(1-1/2)×(1-1/3)×(1-1/4)×……×(1-1/100)=?