2/1*2*3+2/2*3*4+2/3*4*5+2/4*5*6+.2/98*99*100简算 快
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/01 23:36:50
![2/1*2*3+2/2*3*4+2/3*4*5+2/4*5*6+.2/98*99*100简算 快](/uploads/image/z/128717-53-7.jpg?t=2%2F1%2A2%2A3%2B2%2F2%2A3%2A4%2B2%2F3%2A4%2A5%2B2%2F4%2A5%2A6%2B.2%2F98%2A99%2A100%E7%AE%80%E7%AE%97+%E5%BF%AB)
2/1*2*3+2/2*3*4+2/3*4*5+2/4*5*6+.2/98*99*100简算 快
2/1*2*3+2/2*3*4+2/3*4*5+2/4*5*6+.2/98*99*100简算
快
2/1*2*3+2/2*3*4+2/3*4*5+2/4*5*6+.2/98*99*100简算 快
2/1*2*3+2/2*3*4+2/3*4*5+2/4*5*6+.2/98*99*100=(1/(1*2)-1/(2*3))+(1/(2*3)-1/(3*4)).+(1/(98*99)-1/(99*100))=1/2-1/(99*100)=(50*99-1)/(99*100)=4949/9900