2/3+2/15+2/35+2/63简便计算
问题描述:
2/3+2/15+2/35+2/63简便计算
答
2/3+2/15+2/35+2/63
=1-1/3+1/3-1/5+1/5-1/7+1/7-1/9
=1-1/9
=8/9