[問題]幾何題63
由 tangpakchiu 於 星期二 十一月 06, 2007 6:12 am
#ed_op#DIV#ed_cl##ed_op#IMG alt="image file name: 2k48c4d99a67.gif" src="http://yll.loxa.edu.tw/phpBB2/richedit/upload/2k48c4d99a67.gif" border=0#ed_cl##ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl# #ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#如圖,ABCD為一convex四邊形,對角線相交於O,過O作FE//AB,ED交AC於N,FC交BD於M,求證MN//AB。#ed_op#/DIV#ed_cl#