Question

1/11X13x15+1/13x15x17+......+1/29x31x33

Answer 1

你好！
4(1/(31*33*13)
=
20/13x15x17+1/11X13x15+1/......+1/4
(1/11X13
-
1/31x33)
=
1/11X13
-
1/..+
1/4(1/29X31
-
1/31x33)
=
1/29x31x33=
1/4
(3*31-13)/13x15)
+
1/4(1/13x15
-
1/15x17)+
..;13299
答：最后等于20/
希望对你有所帮助，望采纳。

Answer 2

1/11X13x15+1/13x15x17+......+1/29x31x33= 1/4(1/11X13 - 1/13x15) + 1/4(1/13x15 - 1/15x17)+ ....+ 1/4(1/29X31 - 1/31x33)

= 1/4 (1/11X13 - 1/31x33)
= 1/4 (3*31-13)/(31*33*13)
= 20/13299
答：最后等于20/13299

Answer 3

= 1/4(1/11X13 - 1/13x15) + 1/4(1/13x15 - 1/15x17)+ ....+ 1/4(1/29X31 - 1/31x33)

= 1/4 (1/11X13 - 1/31x33)
= 1/4 (3*31-13)/(31*33*13)
= 20/13299