已知角ABC，求作一个角，使它等于二分之一角BAC（要求用尺规作图，并写出作法） 如图，已知∠ABC，求作一个角，使它等于½∠ABC...
\u5982\u56fe,\u5df2\u77e5\u2220ABC,\u6c42\u505a\u4e00\u4e2a\u89d2,\u4f7f\u5b83\u7b49\u4e8e\u4e8c\u5206\u4e4b\u4e00\u2220ABC\u3002\uff08\u8981\u6c42\u7528\u5c3a\u89c4\u4f5c\u56fe\uff0c\u5e76\u7ed9\u51fa\u4f5c\u6cd5\uff09\u65b9\u6cd5\u633a\u591a\u7684\uff0c\u6211\u63d0\u4f9b\u4e24\u79cd\u65b9\u6cd5\uff1a
1\u3001\u5229\u7528\u5c3a\u5b50\u523b\u5ea6\uff0c\u505a\u2220ABC\uff0c\u4ee5B\u4e3a\u4e00\u7aef\u70b9\uff0c\u505aBA=BC\u957f\uff0c\u8fde\u63a5AC\uff0c\u6d4b\u91cf \u505aAC\u4e2d\u70b9D\uff0c\u8fde\u63a5BD\uff0c
\u5219\u7ebfBD\u53ef\u4ee5\u5e73\u5206\u2220ABC
2\u3001\u5229\u7528\u5706\u89c4\uff0c\u5728\u2220ABC\u7684\u7aef\u70b9B\u4e3a\u5706\u5fc3\uff0c\u4ee5\u4efb\u610f\u957f\u4e3a\u534a\u5f84\u5728BA\u3001BC\u8fb9\u4e0a\u753b\u4e24\u70b9\u5206\u522b\u4ea4D\u3001E\u70b9\uff0c
\u518d\u8fde\u63a5DE\uff1b\u518d\u5206\u522b\u4ee5D\u3001E\u4e24\u70b9\u4e3a\u5706\u5fc3\uff0c\u4ee5\u4efb\u610f\u957f\u4e3a\u534a\u5f84\uff0c\u5728DE\u8fde\u7ebf\u4e0a\u4ea4\u4e0e\u4e00\u70b9F\uff0c\u8fde\u63a5BF\uff0c
\u5219\u7ebf\u6bb5BF\u5c31\u5e73\u5206\u2220ABC
\u4ee5\u2220ABC\u7684\u9876\u70b9\u4e3a\u5706\u5fc3\uff0c\u7528\u5c3a\u89c4\u5728\u89d2\u7684\u4e24\u8fb9\u4e0a\u753b\u51fa\u4ea4\u70b9
\u518d\u4ee5\u4ea4\u70b9\u4e3a\u5706\u5fc3\uff0c\u7528\u5c3a\u89c4\u5728\u89d2\u5185\u753b\u51fa\u4ea4\u70b9\uff0c
\u8fde\u63a5\u4ea4\u70b9\u548c\u89d2\u5b9a\u70b9\uff0c\u5c31\u5c06\u2220ABC\u5e73\u5206\u4e3a½\u2220BAC
\u5982\u679c\u662f\u53e6\u5916\u753b\u89d2\u7684\u8bdd\uff0c\u53ef\u4ee5\u5206\u522b\u5728\u4ee5\u2220BAC \u5b9a\u70b9 \u548c \u53e6\u5916\u4e00\u70b9\u753b\u5706
\u5728 ½\u2220BAC \u4e0a\u7528\u5c3a\u89c4\u622a\u53d6\u7384\u957f\uff0c\u5728 \u53e6\u5916\u5706\u4e0a\u753b\u51fa\u540c\u6837\u7384\u957f\u3002
\u8fde\u63a5\u5706\u5fc3\u548c\u7384\u4e0e\u5706\u7684\u4ea4\u70b9\uff0c\u5373\u53ef\u753b\u51fa½\u2220BAC \u7684\u89d2\u3002
是角bac吗？
错了吧
abc吧？
角平分线
很简单的
绛旓細鍏堟妸瑙BAC鐨勮骞冲垎绾夸綔鍑烘潵 鍦ㄧ敤寮у害鐢昏
绛旓細杩炴帴浜ょ偣鍜岃瀹氱偣锛屽氨灏嗏垹ABC骞冲垎涓½鈭燘AC 濡傛灉鏄彟澶栫敾瑙掔殑璇濓紝鍙互鍒嗗埆鍦ㄤ互鈭燘AC 瀹氱偣 鍜 鍙﹀涓鐐圭敾鍦 鍦 ½鈭燘AC 涓婄敤灏鸿鎴彇鐜勯暱锛屽湪 鍙﹀鍦嗕笂鐢诲嚭鍚屾牱鐜勯暱銆傝繛鎺ュ渾蹇冨拰鐜勪笌鍦嗙殑浜ょ偣锛屽嵆鍙敾鍑½鈭燘AC 鐨勮銆
绛旓細杩炴帴浜ょ偣鍜岃瀹氱偣锛屽氨灏嗏垹ABC骞冲垎涓½鈭燘AC 濡傛灉鏄彟澶栫敾瑙掔殑璇濓紝鍙互鍒嗗埆鍦ㄤ互鈭燘AC 瀹氱偣 鍜 鍙﹀涓鐐圭敾鍦 鍦 ½鈭燘AC 涓婄敤灏鸿鎴彇鐜勯暱锛屽湪 鍙﹀鍦嗕笂鐢诲嚭鍚屾牱鐜勯暱銆傝繛鎺ュ渾蹇冨拰鐜勪笌鍦嗙殑浜ょ偣锛屽嵆鍙敾鍑½鈭燘AC 鐨勮銆
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绛旓細濡備笅鍥撅細锛屸垹MEN=鈭2ABC锛
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