速速速速速速速速速速速速速速速速速速速速速速!
来源:学生作业帮 编辑:百度作业网作业帮 分类:数学作业 时间:2024/07/31 16:21:48
速速速速速速速速速速速速速速速速速速速速速速!
(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)
这个是简算,怎么能用计算机!
(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)
这个是简算,怎么能用计算机!
![速速速速速速速速速速速速速速速速速速速速速速!](/uploads/image/z/5140716-60-6.jpg?t=%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%E9%80%9F%21)
这个我前几天学清华少儿数学时学过.
(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)
=A乘 (1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=(B+1)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=B乘(1/2+1/3+1/4+1/5)+1乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=B乘(1/2+1/3+1/4+1/5)+1乘(1/2+1/3+1/4+1/5)-(1/2+1/3+1/4+1/5)乘B+B
=(1/2+1/3+1/4+1/5)-(1/2+1/3+1/4)
=1/5
(1+1/2+1/3+1/4)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘(1/2+1/3+1/4)
=A乘 (1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=(B+1)乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=B乘(1/2+1/3+1/4+1/5)+1乘(1/2+1/3+1/4+1/5)-(1+1/2+1/3+1/4+1/5)乘B
=B乘(1/2+1/3+1/4+1/5)+1乘(1/2+1/3+1/4+1/5)-(1/2+1/3+1/4+1/5)乘B+B
=(1/2+1/3+1/4+1/5)-(1/2+1/3+1/4)
=1/5