1/2+1/6+2/15+2/35+4/77等于多少?(列方程解)

问题描述:

1/2+1/6+2/15+2/35+4/77等于多少?(列方程解)

=1/1*2+1/2*3+2/3*5+2/5*7+4/7*11
=1-1/2+1/2-1/3+1/3-1/5+1/5-1/7+1/7-1/11
=1-1/11
=10/11