一副直角三角板如图放置，点C在FD的延长线上，AB∥CF，∠F=∠ACB=90°，∠E=45°，∠A=60°，AC=10，试求 一副直角三角板如图放置，点C在FD的延长线上，AB // C...

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\u89e3\uff1a\u8fc7\u70b9B\u4f5cBM\u22a5FD\u4e8e\u70b9M. \u5728\u25b3ACB\u4e2d\uff0c\u2220ACB=90\u00b0\uff0c\u2220A= 60\u00b0\uff0cAC=10\uff0c \u2234\u2220ABC= 30\u00b0\uff0cBC=ACtan60\u00b0=10 \uff0c \u2235AB//CF\uff0c\u2234\u2220BCM= 30\u00b0\uff0c \u2235BM=BC\u00b7sin30\u00b0=10\u00d7 =5 \uff0cCM=BC\u00b7cos30\u00b0=10\u00d7 =15\uff0c\u5728\u25b3EFD\u4e2d\uff0c\u2220F=90\u00b0\uff0c\u2220E=45\u00b0\uff0c\u2234\u2220EDF= 45\u00b0\uff0c\u2234MD= BM= 5 \uff0c\u2234CD= CM-MD=15-5 .

涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈭F,鈭燜=鈭燗CB=90掳... 绛旓細锛1锛12 锛涳紙2锛12锛4 璇曢鍒嗘瀽锛氾紙1锛夌敱棰樻剰鍙煡鈻矨CB涓虹瓑鑵鐩磋涓夎褰紝鏍规嵁绛夎叞鐩磋涓夎褰㈢殑鎬ц川姹傝В鍗冲彲锛涳紙2锛夎繃鐐笲浣淏M鈯D浜庣偣M锛屾牴鎹钩琛岀嚎鐨勬ц川鍙眰寰桞M銆丆M鐨勯暱锛屽啀鍦ㄢ柍EFD涓紝鏍规嵁涓夎褰㈢殑鍐呰鍜屽畾鐞嗘眰寰椻垹EDF锛60掳锛屾牴鎹垹EDF鐨勬鍒囧嚱鏁板嵆鍙眰寰桵D鐨勯暱锛屼粠鑰屽彲浠ユ眰寰楃粨鏋... 涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈭F,鈭燜=鈭燗CB=90掳... 绛旓細鍦鐩磋涓夎褰BAC涓牴鎹嬀鑲″畾鐞嗗彲姹傚緱BC鐨勯暱锛屼粠鑰屽彲姹傚緱MB鐨勯暱锛屽湪鐩磋涓夎褰MC涓牴鎹嬀鑲″畾鐞嗗彲姹傚緱CM鐨勯暱锛屽啀鏍规嵁绛夎叞鐩磋涓夎褰㈢殑鎬ц川姹傚緱MD鐨勯暱锛屼粠鑰屽彲浠ユ眰寰楃粨鏋.杩囩偣B浣淏M鈯D浜庣偣M锛 鍦ㄢ柍ACB涓紝鈭燗CB=90掳锛 瑙鐩磋涓夎褰,姹傝繃绋嬨 绛旓細涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆锛岀偣C鍦FD鐨勫欢闀跨嚎涓婏紝AB鈭F锛屸垹F=鈭燗CB=90掳锛屸垹E=45掳锛屸垹A=60掳锛孉C=10锛岃瘯姹侰D鐨勯暱锛庛愯В鏋愩戣繃鐐笲浣淏M鈯D浜庣偣M锛屾牴鎹鎰忓彲姹傚嚭BC鐨勯暱搴︼紝鐒跺悗鍦ㄢ柍EFD涓彲姹傚嚭鈭燛DF=45掳锛岃繘鑰屽彲寰楀嚭绛旀锛庛愮瓟妗堛戣В锛氳繃鐐笲浣淏M鈯D浜庣偣M锛屽湪鈻矨CB涓紝鈭燗CB=90掳... 涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB // CF,鈭燜 =鈭燗CB= 9... 绛旓細瑙ｏ細杩囩偣B浣淏M鈯D浜庣偣M. 鍦ㄢ柍ACB涓紝鈭燗CB=90掳锛屸垹A= 60掳锛孉C=10锛 鈭粹垹ABC= 30掳锛孊C=ACtan60掳=10 锛 鈭礎B//CF锛屸埓鈭燘CM= 30掳锛 鈭礏M=BC路sin30掳=10脳 =5 锛孋M=BC路cos30掳=10脳 =15锛屽湪鈻矱FD涓紝鈭燜=90掳锛屸垹E=45掳锛屸埓鈭燛DF= 45掳锛屸埓MD= BM=... 涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈭F,鈭燜=鈭犫垹ACB=90... 绛旓細瑙ｏ細杩囩偣B浣淏M鈯D浜庣偣M 鍦ㄢ柍ACB涓紝鈭燗CB=90掳锛屸垹A=60掳锛孉C=10锛屸埓鈭燗BC=30掳锛孊C=AC脳tan60掳=10鏍瑰彿3 锛屸埖AB鈭F锛屸埓BM=BC脳sin30掳=10 鏍瑰彿3脳1/2 =5鏍瑰彿3 锛孋M=BC脳cos30掳=10鏍瑰彿3脳鏍瑰彿3/2锛15锛屽湪鈻矱FD涓紝鈭燜=90掳锛屸垹E=45掳锛屸埓鈭燛DF=45掳锛屸埓MD=BM=5鏍瑰彿... (2012?宸翠腑)涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈭F,鈭燜=... 绛旓細瑙ｏ細杩囩偣B浣淏M鈯D浜庣偣M锛屽湪鈻矨CB涓紝鈭燗CB=90掳锛屸垹A=45掳锛孉C=122锛屸埓BC=AC=122鈭礎B鈭F锛屸埓BM=BC脳sin45掳=122脳22=12CM=BM=12锛屽湪鈻矱FD涓紝鈭燜=90掳锛屸垹E=30掳锛屸埓鈭燛DF=60掳锛屸埓MD=BM梅tan60掳=43锛屸埓CD=CM-MD=12-43锛... 涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈥朇F,鈭燜=鈭燗CB=90掳... 绛旓細鈭燗BD=45掳锛屸垹ABC=30掳锛屸埓鈭燚BC=15掳 tan鈭燚BC=tan15掳=tan(60掳-45掳)=(tan60掳- tan45掳)/(1+ tan60掳*tan45掳)=(鏍瑰彿3 -1)/(1+鏍瑰彿3锛=(鏍瑰彿3-1)*(鏍瑰彿3-1)/[(鏍瑰彿3+1)(鏍瑰彿3-1)]=(4-2鏍瑰彿3)/2 =2-鏍瑰彿3 ... 涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈭F,鈭燜=鈭燗CB=90掳... 绛旓細瑙ｏ細鈭2=鈭1=鈭燗=45掳锛屸垹3=60掳锛孊C=AC= 锛屼綔BH鈯C浜庣偣H锛屽垯BH=CH= BC=12锛孯t鈻矪DH涓紝DH=BH梅tan鈭3=12 梅 =4 锛屸埓 CD=CH-DH=12-4 涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈭F,鈭燜=鈭燗CB=90掳... 绛旓細杩嘽浣淎b鍨傜嚎锛屽瀭瓒充负G銆傝繃B浣淐F鍨傜嚎锛屽瀭瓒充负M銆侫c=12*Sqrt锛2锛夛紝鍒欙紝Ab=24锛孊G= 12=MC銆傗垹BCM=鈭燗BC=45搴︼紝鍙堚垹BMC=90搴︼紝鍒橫C=BM=12 鍙堬紝鈭燚BM=鈭燛=30搴︼紝鍒欙紝Md=BM/sqrt锛3锛夛紝鍒欙紝CD=Mc-MD=12-12/sqrt(3)Ps锛泂qrt锛堬級琛ㄧず鏍瑰彿锛 (2012?宸翠腑)涓鍓洿瑙掍笁瑙掓澘濡傚浘鏀剧疆,鐐笴鍦FD鐨勫欢闀跨嚎涓,AB鈭F,鈭燜=... 绛旓細濡傚浘鎵绀猴紝杩囩偣B浣淐F鐨勫瀭绾緽G锛屽瀭瓒充负G銆傚洜涓篈B鈭F锛屾墍浠モ垹A=鈭燗BC=鈭燘CF=45掳锛屾墍浠モ柍BCG涓虹瓑鑵鐩磋涓夎褰紝鍥犱负AC=BC=122锛屾墍浠G=CG=61鈭2锛屽張鍥犱负鍦ㄧ洿瑙掍笁瑙掑舰DEF涓垹E=30掳锛屾墍浠モ垹EDF=60掳锛屾墍浠ュ湪鐩磋涓夎褰DG涓畻寰桪G=61鈭6/3锛屾墍浠D=CG-DG=(61鈭2)-(61鈭6/3)=(183鈭2... 扩展阅读：角尺使用视频 ... 45度弯头斜边的算法 ... 三角尺图片大全 ... 三角尺的度数图 ... 小学生三角板图片 ... 把09填入十个小三角形中 ... 楼梯连体三角板教程 ... 懒人三角计算器 ... 求斜边最简单方法 ... 本站交流只代表网友个人观点，与本站立场无关 欢迎反馈与建议，请联系电邮 2024© 车视网