1/1x3 +1/3x5 +1/5x7+ .+ 1/49x51
=(1/2)x[(1-1/3)+(1/3-1/5)+(1/5-1/7)+.+(1/49-1/51)]
=(1/2)x(1-1/51)
=(1/2)x (50/51)
=25/51
如还不明白,请继续追问.
手机提问的朋友在客户端右上角评价点【满意】即可.
1/1x3 +1/3x5 +1/5x7+ .+ 1/49x51
=(1/2)x[(1-1/3)+(1/3-1/5)+(1/5-1/7)+.+(1/49-1/51)]
=(1/2)x(1-1/51)
=(1/2)x (50/51)
=25/51
如还不明白,请继续追问.
手机提问的朋友在客户端右上角评价点【满意】即可.