(1/5+1/7+1/9+1/11)*(1/7+1/9+1/11+1/13)-(1/5+1/7+1/9+1/11+1/13)*(1/7+1/9+1/11)简便运算

来源:学生作业学帮网 编辑:学帮网 时间:2024/05/19 01:00:51

(1/5+1/7+1/9+1/11)*(1/7+1/9+1/11+1/13)-(1/5+1/7+1/9+1/11+1/13)*(1/7+1/9+1/11)
简便运算

提取=(1/5+1/7+1/9+1/11)*(1/7+1/9+1/11)+(1/5+1/7+1/9+1/11)*1/13-(1/5+1/7+1/9+1/11)*(1/7+1/9+1/11)-1/13*(1/7+1/9+1/11)=(1/5+1/7+1/9+1/11)*1/13-1/13*(1/7+1/9+1/11)=1/13*(1/5+1/7+1/9+1/11-1/7+1/9+1/11)=1/13*1/5=1/65

未采纳,编辑掉