怎样用圆规和直尺做线段的黄金分割点，画五角星 已知线段AB=a，用直尺和圆规求作这条线段的黄金分割点C
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绛旓細- 浣跨敤鍦嗚鍦ㄥ熀鍑嗙嚎鐨勪换鎰忎竴绔敾涓涓渾寮с- 鍦ㄥ渾寮х殑鍙︿竴绔紝鍒╃敤鐩村昂鍜屽渾瑙勶紝鐢讳竴鏉′笌鍩哄噯绾夸氦鍙夌殑绾挎銆- 杩欐潯浜ゅ弶绾挎涓庡熀鍑嗙嚎鐨勪氦鐐癸紝鍗充负榛勯噾鍒嗗壊鐐广2. 浣跨敤璁＄畻鍣ㄧ‘瀹氶粍閲戞瘮渚嬶細- 鎵撳紑璁＄畻鍣紝骞惰緭鍏0.618锛堣繖鏄粍閲戞瘮渚嬬殑鏁板硷級銆- 灏嗚绠楀櫒鏄剧ず鐨勫间綔涓烘瘮渚嬶紝搴旂敤浜庣粯鍒堕粍閲戝垎鍓层- ...
绛旓細涓嬮潰鏄竴绉嶇敾鍑榛勯噾鍒嗗壊鐐圭殑鍩烘湰姝ラ鏂规硶锛屼笉闇瑕佸鏉傜殑鏁板璁＄畻锛屽彧闇鐢ㄥ昂鍜鍦嗚鍗冲彲锛1. **鐢绾挎AB**锛氶鍏堢敾涓鏉￠暱搴︿负$4\text{cm}$鐨勭嚎娈碉紝鏍囪涓篈B銆2. **鏋勫缓姝ｆ柟褰**锛氫互绾挎AB涓轰竴杈癸紝鐢讳竴涓鏂瑰舰ABCD锛堝亣璁綝鏄疉鐐圭殑瀵硅锛孋鏄疊鐐圭殑瀵硅锛夈3. **鍒嗗壊姝ｆ柟褰**锛氬皢姝ｆ柟褰BCD...
绛旓細1.鍏堢敤鐩村昂浣滅洿绾縧锛鐢ㄥ渾瑙鍦ㄧ洿绾夸笂鎴彇AB锛屼娇AB=a(宸茬煡绾挎鐨闀)2.杩嘇鐐瑰紩AB鐨勫瀭绾(杩欎釜搴旇涓嶇敤鎴戝璁蹭簡鍚)3.鍦ㄥ瀭绾夸笂鎴彇AC锛屼娇AC=a/2,鐒跺悗杩炴帴BC銆4.浠涓哄渾蹇冿紝CA鐨勯暱涓哄崐寰勭敾寮э紝浜ょ嚎娈礏C浜庝竴鐐癸紝鏍囦綔D銆5.鏈鍚庝互B涓哄渾蹇冿紝BD鐨勯暱涓哄崐寰勭敾寮э紝浜ょ嚎娈礎B浜庝竴鐐笶锛 鍒橢鍗充负绾挎A...
绛旓細瑙ｏ細浣滄硶锛氾紙1锛夊欢闀绾挎AB鑷矲锛屼娇AB=BF锛屽垎鍒互A銆丗涓哄渾蹇冿紝浠ュぇ浜庣瓑浜庣嚎娈礎B鐨勯暱涓哄崐寰勪綔寮э紝涓ゅ姬鐩镐氦浜庣偣G锛岃繛鎺G锛屽垯BG鈯B锛屽湪BG涓婂彇鐐笵锛屼娇BD=AB2锛涳紙2锛夎繛鎺D锛屽湪AD涓婃埅鍙朌E=DB锛庯紙3锛夊湪AB涓婃埅鍙朅C=AE锛庡鍥撅紝鐐笴灏辨槸绾挎a鐨勯粍閲鍒嗗壊鐐癸紟
绛旓細鏂规硶涓:棣栧厛鍦ㄧ焊涓婄敤鍦嗚鐢讳釜鍦,鐒跺悗鐢诲嚭鍦嗙殑涓ゆ潯鐩镐簰鍨傜洿鐨勭洿寰凙C涓嶣D锛涗箣鍚庡垎鍒敤C銆丏浣滃渾蹇,鐢ㄧ洿寰凚D鐨勫崐寰勪綔寮,涓ゅ姬浜ゅ湪E鐐.鍒橭E渚胯繎浼肩瓑浜庡渾鐨勫唴鎺ユ浜旇竟褰箣杈归暱.鑷狝鐐瑰紑濮,鐢∣E浣滃崐寰勫湪鍦嗗懆涓婁緷娆℃埅鍑哄洓涓偣鏉,杩炴帴鐩搁偦鐨勪簩涓偣,寰楀埌鐨勯偅涓浜旇竟褰究鍙仛鍦嗙殑鍐呮帴姝ｄ簲杈瑰舰(鍥犱负瀹冪殑浜...
绛旓細1.鍏堢敤鐩村昂浣滅洿绾縧锛鐢ㄥ渾瑙鍦ㄧ洿绾夸笂鎴彇AB锛屼娇AB=a(宸茬煡绾挎鐨闀匡級2.杩嘇鐐瑰紩AB鐨勫瀭绾匡紙杩欎釜搴旇涓嶇敤鎴戝璁蹭簡鍚э級3.鍦ㄥ瀭绾夸笂鎴彇AC锛屼娇AC=a/2,鐒跺悗杩炴帴BC銆4.浠涓哄渾蹇冿紝CA鐨勯暱涓哄崐寰勭敾寮э紝浜ょ嚎娈礏C浜庝竴鐐癸紝鏍囦綔D銆5.鏈鍚庝互B涓哄渾蹇冿紝BD鐨勯暱涓哄崐寰勭敾寮э紝浜ょ嚎娈礎B浜庝竴鐐笶锛 鍒橢鍗充负...
绛旓細1.鍏堢敤鐩村昂浣滅洿绾縧锛鐢ㄥ渾瑙鍦ㄧ洿绾夸笂鎴彇AB锛屼娇AB=a(宸茬煡绾挎鐨闀匡級2.杩嘇鐐瑰紩AB鐨勫瀭绾匡紙杩欎釜搴旇涓嶇敤鎴戝璁蹭簡鍚э級3.鍦ㄥ瀭绾夸笂鎴彇AC锛屼娇AC=a/2,鐒跺悗杩炴帴BC銆4.浠涓哄渾蹇冿紝CA鐨勯暱涓哄崐寰勭敾寮э紝浜ょ嚎娈礏C浜庝竴鐐癸紝鏍囦綔D銆5.鏈鍚庝互B涓哄渾蹇冿紝BD鐨勯暱涓哄崐寰勭敾寮э紝浜ょ嚎娈礎B浜庝竴鐐笶锛屽垯E鍗充负绾挎...
绛旓細鏂规硶涓:棣栧厛鍦ㄧ焊涓鐢ㄥ渾瑙鐢讳釜鍦嗭紝鐒跺悗鐢诲嚭鍦嗙殑涓ゆ潯鐩镐簰鍨傜洿鐨勭洿寰凙C涓嶣D锛涗箣鍚庡垎鍒敤C銆丏浣滃渾蹇冿紝鐢ㄧ洿寰凚D鐨勫崐寰勪綔寮э紝涓ゅ姬浜ゅ湪E鐐广傚垯OE渚胯繎浼肩瓑浜庡渾鐨勫唴鎺ユ浜旇竟褰箣杈归暱銆傝嚜A鐐瑰紑濮嬶紝鐢∣E浣滃崐寰勫湪鍦嗗懆涓婁緷娆℃埅鍑哄洓涓偣鏉ワ紝杩炴帴鐩搁偦鐨勪簩涓偣锛屽緱鍒扮殑閭ｄ釜姝ｄ簲杈瑰舰渚垮彨鍋氬渾鐨勫唴鎺ユ浜旇竟褰(鍥犱负瀹...
绛旓細涓銆佸厛鐢诲嚭AB鐐圭殑涓偣C;浜屻佷綔AB鐨勫瀭绾緼D浜B浜嶢鐐;涓夈佷互AC涓哄崐寰凙涓哄渾蹇冧綔鍦嗕氦AD浜嶦;鍥涖佽繛缁揃E;浜斻佷粠A鐐逛綔BE鐨勫瀭绾夸氦BE浜嶧;鍏佷互A鐐逛负鍦嗗績AF涓哄崐寰勪綔鍦嗕氦AB浜嶨鐐;涓冦佷綔GB鐨勪腑鐐逛氦GB浜嶩鐐癸紝H鐐逛负AB鐨勯粍閲鍒嗗壊鐐广
绛旓細1銆佸噯澶囧伐浣滐細鍑嗗鍦嗚銆侀搮绗斻灏哄瓙鍜屼竴寮犵櫧绾搞2銆佺敾绾挎锛氱敾涓鏉＄嚎娈碉紝闀垮害鏍规嵁鎯宠鐨勪簲瑙掓槦澶у皬鏉ュ喅瀹氾紝杩欐潯绾挎灏嗘垚涓轰簲瑙掓槦鐨勪腑鍨傜嚎銆3銆佺敾寮х嚎锛浣跨敤鍦嗚鍦ˋ銆丅涓ょ偣涔嬮棿鐢诲姬锛屽姬绾块暱搴﹀簲澶т簬绾挎AB闀垮害鐨勪竴鍗婏紝纭繚涓婁笅鍚勬湁涓涓氦鐐广4銆佽繛鎺ヤ氦鐐癸細鐢ㄨ櫄绾胯繛鎺ヨ繖涓や釜浜ょ偣锛屽苟鍨傜洿浜庣偣D銆5銆佺敾...
