由 jackhoung 於 星期四 七月 27, 2006 2:28 pm
#ed_op#DIV#ed_cl#連接AB,BF#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#角PDC=角PAB=角PFB#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#角BPE=角BFE#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#角PEF=角PDC+角BPE=角PFB+角BFE=角PEF#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#所以#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#PE=PF#ed_op#/DIV#ed_cl#