1/2+1/6+1/12+1/20+1/30+1/42=
来源:学生作业帮助网 编辑:作业帮 时间:2024/09/01 19:44:10
![1/2+1/6+1/12+1/20+1/30+1/42=](/uploads/image/z/6810262-70-2.jpg?t=1%2F2%2B1%2F6%2B1%2F12%2B1%2F20%2B1%2F30%2B1%2F42%3D)
x
0CBUK]` T0(=pBgvܪ%XJxV[1J>.PǎG{^]ᠾp6ft`=L nY_6N
1/2+1/6+1/12+1/20+1/30+1/42=
1/2+1/6+1/12+1/20+1/30+1/42=
1/2+1/6+1/12+1/20+1/30+1/42=
=1/1×2+1/2×3+1/3×4+1/4×5+1/5×6+1/6×7
=1-1/2+1/2-1/3+1/3-1/4+1/4-1/5+1/5-1/6+1/6-1/7
=1-1/7
=6/7