由 jackhoung 於 星期五 七月 28, 2006 8:04 pm
#ed_op#DIV#ed_cl#連接OC,OA,OB,#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#則角OCD=角OBC=角OAD#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#又#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#角OCA=角OAC#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#所以#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#角ACD=角CAD#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#即#ed_op#/DIV#ed_cl##ed_op#DIV#ed_cl#CD=AD#ed_op#/DIV#ed_cl#