3|4+3|28+3|70+3|130+3|208=找规律计算_数学解答

3|4+3|28+3|70+3|130+3|208=找规律计算

人气：299 ℃　时间：2020-04-27 07:26:07

解答

=3/（1*4）+3/(4*7)+3/（7*10）+.3/(13*16)
=3(1/(1*4)+1/(4*7)+.1/(13*16))
=1-1/4+1/4-1/7+.+1/13-1/16
=1-1/16
=15/16