#ed_op#br#ed_cl#謝謝!...#ed_op#br#ed_cl#亞斯 寫到:過C做AC的垂線與AF的延長線交於G
#ed_op#br#ed_cl#謝謝!...#ed_op#br#ed_cl#亞斯 寫到:過C做AC的垂線與AF的延長線交於G
#ed_op#br#ed_cl#承蒙 亞斯 的提點:#ed_op#br#ed_cl##ed_op#img src="richedit/upload/2k88449de943.png" alt="image file name: 2k88449de943.png" border="0"#ed_cl##ed_op#br#ed_cl##ed_op#span id="convert157079"#ed_cl##ed_op#span class="postbody"#ed_cl#過C作AC的垂線與AF的延長線交於G#ed_op#br#ed_cl##ed_op#/span#ed_cl##ed_op#/span#ed_cl#ΔABD~ΔEAD~ΔCAG (AAA);CG:CA=AD:AB=1:2 => CG=CA/2=CD;#ed_op#br#ed_cl#∴ΔCFD≡ΔCFG (SAS) => 角ADB=角AGC=角FDC。#ed_op#br#ed_cl#tangpakchiu 寫到:#ed_op#div#ed_cl#已知直角等腰三角形ABC中,角A為直角,D是線段AC的中點,AE垂直BD,AE的延長線交BC于F,求證角ADB=角FDC。#ed_op#/div#ed_cl#