1/C5m-1/C6m=7/C7m，求C8m=?
1/C5m-1/C6m=7/C7m，求C8m=?
日期：2006-03-26 12:11:54 人气：3
1/C5m-1/C6m=7/C7m
(c6m-c5m)/c5m*c6m=7/C7m
c5m(c-1)/c5m*c6m=7/c7m
(c-1)/c6m=7/c7m
(c-1)*c7m=c6m*7
c2(平方)-c=7
c2(平方)-c-7=0
(c-1/2)2(平方)-8=0
c-1/2=√8
C=√8+1/2
c8m=(√8+1/2)8m
以上解题基于c8m为c的8m次方
C