规定(3)=2X3X4,(4)=3X4X5,(5)=4X5X6,.如果1/(6)+1/(7)=1/(7)X·,那么· 等于多少
问题描述:
规定(3)=2X3X4,(4)=3X4X5,(5)=4X5X6,.如果1/(6)+1/(7)=1/(7)X·,那么· 等于多少
答
按题设的规律,(6)=5*6*7,(7)=6*7*8,
由等式知·=(7)/(6)+1=(6*7*8)/(5*6*7)+1=13/5