计算,(1/8+1/9+1/10+1/11)x(1/9+1/10+1/11+1/12)-(1/8+1/9+1/10+1/11+1/_数学解答

计算,(1/8+1/9+1/10+1/11)x(1/9+1/10+1/11+1/12)-(1/8+1/9+1/10+1/11+1/12)x(1/9+1/10+1/11)

人气：380 ℃　时间：2019-10-01 02:34:33

解答

设(1/8+1/9+1/10+1/11)=a,1/9+1/10+1/11=b
a（b+1/12）-（a+1/12）*b
=（a-b）/12
=(1/8)/12
=1/96