圆的直径，半径怎么算，求公式已知圆的 圆直径半径怎么算
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2.\u5728\u4e00\u4e2a\u5e73\u9762\u5185\uff0c\u4e00\u52a8\u70b9\u4ee5\u4e00\u5b9a\u70b9\u4e3a\u4e2d\u5fc3\uff0c\u4ee5\u4e00\u5b9a\u957f\u5ea6\u4e3a\u8ddd\u79bb\u65cb\u8f6c\u4e00\u5468\u6240\u5f62\u6210\u7684\u5c01\u95ed\u66f2\u7ebf\u53eb\u505a\u5706\u3002
3.\u5728\u540c\u4e00\u5e73\u9762\u5185\uff0c\u5230\u5b9a\u70b9\u7684\u8ddd\u79bb\u7b49\u4e8e\u5b9a\u957f\u7684\u70b9\u7684\u96c6\u5408\u53eb\u505a\u5706\u3002\u5706\u53ef\u4ee5\u8868\u793a\u4e3a\u96c6\u5408{M||MO|=r},\u5706\u7684\u6807\u51c6\u65b9\u7a0b\u662f(x - a) ² + (y - b) ² = r ²\u3002\u5176\u4e2d\uff0c(a , b)\u662f\u5706\u5fc3\uff0cr \u662f\u534a\u5f84\u3002\u5706\u5f62\u662f\u4e00\u79cd\u5706\u9525\u66f2\u7ebf\uff0c\u7531\u5e73\u884c\u4e8e\u5706\u9525\u5e95\u9762\u7684\u5e73\u9762\u622a\u5706\u9525\u5f97\u5230\u3002
4.\u5706\u662f\u4e00\u79cd\u51e0\u4f55\u56fe\u5f62\u3002\u6839\u636e\u5b9a\u4e49\uff0c\u901a\u5e38\u7528\u5706\u89c4\u6765\u753b\u5706\u3002 \u540c\u5706\u5185\u5706\u7684\u76f4\u5f84\u3001\u534a\u5f84\u957f\u5ea6\u6c38\u8fdc\u76f8\u540c\uff0c\u5706\u6709\u65e0\u6570\u6761\u534a\u5f84\u548c\u65e0\u6570\u6761\u76f4\u5f84\u3002\u5706\u662f\u8f74\u5bf9\u79f0\u3001\u4e2d\u5fc3\u5bf9\u79f0\u56fe\u5f62\u3002\u5bf9\u79f0\u8f74\u662f\u76f4\u5f84\u6240\u5728\u7684\u76f4\u7ebf\u3002 \u540c\u65f6\uff0c\u5706\u53c8\u662f\u201c\u6b63\u65e0\u9650\u591a\u8fb9\u5f62\u201d\uff0c\u800c\u201c\u65e0\u9650\u201d\u53ea\u662f\u4e00\u4e2a\u6982\u5ff5\u3002\u5f53\u591a\u8fb9\u5f62\u7684\u8fb9\u6570\u8d8a\u591a\u65f6\uff0c\u5176\u5f62\u72b6\u3001\u5468\u957f\u3001\u9762\u79ef\u5c31\u90fd\u8d8a\u63a5\u8fd1\u4e8e\u5706\u3002\u6240\u4ee5\uff0c\u4e16\u754c\u4e0a\u6ca1\u6709\u771f\u6b63\u7684\u5706\uff0c\u5706\u5b9e\u9645\u4e0a\u53ea\u662f\u6982\u5ff5\u6027\u7684\u56fe\u5f62\u3002
\u5728\u540c\u4e00\u5e73\u9762\u5185\u5230\u5b9a\u70b9\u7684\u8ddd\u79bb\u7b49\u4e8e\u5b9a\u957f\u7684\u70b9\u7684\u96c6\u5408\u53eb\u505a\u5706\u8fd9\u4e2a\u5b9a\u70b9\u53eb\u505a\u5706\u7684\u5706\u5fc3\u3002
\u5706\u5f62\u4e00\u5468\u7684\u957f\u5ea6\uff0c\u5c31\u662f\u5706\u7684\u5468\u957f\u3002\u80fd\u591f\u91cd\u5408\u7684\u4e24\u4e2a\u5706\u53eb\u7b49\u5706\u3002
\u5706\u662f\u4e00\u4e2a\u6b63n\u8fb9\u5f62\uff08n\u4e3a\u65e0\u9650\u5927\u7684\u6b63\u6574\u6570\uff09\uff0c\u8fb9\u957f\u65e0\u9650\u63a5\u8fd10\u4f46\u6c38\u8fdc\u65e0\u6cd5\u7b49\u4e8e0\u3002
\u5df2\u77e5\u5706\u7684\u5468\u957f\uff0c\u6c42\u5706\u7684\u76f4\u5f84\u6216\u534a\u5f84\u65b9\u6cd5\u5982\u4e0b\uff1a
1\u3001\u5df2\u77e5\u5706\u7684\u5468\u957f\uff0c\u6c42\u5706\u7684\u76f4\u5f84\uff1a
\u76f4\u5f84 = \u5468\u957f \u00f7 \u03c0\uff083.14\uff09
2\u3001\u5df2\u77e5\u5706\u7684\u5468\u957f\uff0c\u6c42\u5706\u7684\u534a\u5f84\uff1a
\u534a\u5f84 = \u5468\u957f \u00f7 2 \u00f7 \u03c0\uff083.14\uff09
\u4f9d\u636e\u662f\uff1a\u5706\u5468\u7387\u3002
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\u6269\u5c55\u8d44\u6599
\u4e0e\u5706\u76f8\u5173\u7684\u516c\u5f0f\uff1a
1\u3001\u5706\u9762\u79ef\uff1aS=\u03c0r²\uff0cS=\u03c0(d/2)²\u3002\uff08d\u4e3a\u76f4\u5f84\uff0cr\u4e3a\u534a\u5f84\uff09\u3002
2\u3001\u534a\u5706\u7684\u9762\u79ef\uff1aS\u534a\u5706=(\u03c0r^2)/2\u3002\uff08r\u4e3a\u534a\u5f84\uff09\u3002
3\u3001\u5706\u73af\u9762\u79ef\uff1aS\u5927\u5706-S\u5c0f\u5706=\u03c0(R^2-r^2)(R\u4e3a\u5927\u5706\u534a\u5f84\uff0cr\u4e3a\u5c0f\u5706\u534a\u5f84)\u3002
4\u3001\u5706\u7684\u5468\u957f\uff1aC=2\u03c0r\u6216c=\u03c0d\u3002\uff08d\u4e3a\u76f4\u5f84\uff0cr\u4e3a\u534a\u5f84\uff09\u3002
5\u3001\u534a\u5706\u7684\u5468\u957f\uff1ad+(\u03c0d)/2\u6216\u8005d+\u03c0r\u3002\uff08d\u4e3a\u76f4\u5f84\uff0cr\u4e3a\u534a\u5f84\uff09\u3002
6\u3001\u6247\u5f62\u6240\u5728\u5706\u7684\u9762\u79ef\u9664\u4ee5360\u518d\u4e58\u4ee5\u6247\u5f62\u5706\u5fc3\u89d2\u7684\u89d2\u5ea6n\uff0c\u5982\u4e0b\uff1a
S=n/360\u00d7\u03c0r²
S=\u03c0r²\u00d7L/2\u03c0r=Lr/2\uff08L\u4e3a\u5f27\u957f\uff0cr\u4e3a\u6247\u5f62\u534a\u5f84\uff09
s=πrr 圆的面积=半径×半径×圆周率
圆的面积=3.14×半径的平方
所以半径的平方=圆的面积÷3.14
更号求出来的数，就是半径
半径乘以二就是直径
绛旓細鍗婂緞 = 鍛ㄩ暱 梅 2 梅 蟺锛3.14锛変緷鎹槸锛氬渾鍛ㄧ巼銆傚渾鍛ㄧ巼锛圥i锛夋槸鍦嗙殑鍛ㄩ暱涓庣洿寰勭殑姣斿硷紝涓鑸敤甯岃厞瀛楁瘝蟺锛堣浣減脿i锛夎〃绀猴紝蟺鏄竴涓父鏁帮紙绾︾瓑浜3.141592654锛夛紝鏄唬琛ㄥ渾鍛ㄩ暱鍜岀洿寰勭殑姣斿笺傚畠鏄竴涓棤鐞嗘暟锛屽嵆鏃犻檺涓嶅惊鐜皬鏁般傚湪鏃ュ父鐢熸椿涓紝閫氬父閮界敤3.14浠ｈ〃鍦嗗懆鐜囧幓杩涜杩戜技璁＄畻銆
绛旓細鍦嗙殑璁＄畻鍏紡锛氬渾鐨勫懆闀=鐩村緞脳蟺=2脳鍗婂緞脳蟺锛屽渾鐨勯潰绉=鍗婂緞²脳蟺銆(蟺鏄渾鍛ㄧ巼)鐩村緞鏄粡杩囧渾蹇冪殑鐩寸嚎涓庡渾鍛ㄤ袱绔浉浜ょ殑绾挎銆傚崐寰勬槸鍦嗗績鍒板渾鍛ㄧ嚎娈点傜洿寰=2脳鍗婂緞銆傚渾鍛ㄧ巼鏄渾鐨勫懆闀夸笌鐩村緞鐨勬瘮鐜囥
绛旓細鍦嗗懆闀緾锛屽崐寰r锛岀洿寰D =2r
绛旓細杩欐牱
绛旓細鍦嗗湪鏍囧噯鏂圭▼寮忎笅鐨勫渾蹇冨潗鏍囦负:锛坅,b锛,鍗婂緞鍏紡涓猴細r=鈭歔(x-a)^2+(y-b)^2]銆傚渾鍦ㄤ竴鑸柟绋嬪紡涓嬬殑鍦嗗績鍧愭爣涓猴細锛-D/2,-E/2锛夛紝鍗婂緞鍏紡涓猴細r=鈭歔锛圖^2+E^2-4F锛塢/2銆傛爣鍑嗘柟绋嬪渾鐨勬爣鍑嗘柟绋嬩负锛(x-a)^2+(y-b)^2=r^2 锛屽叾涓璦鍜宐鍒嗗埆鏄钩闈㈠潗鏍囩郴涓垎鍒窛绂粂杞村拰x杞寸殑璺濈...
绛旓細c=蟺d=2蟺r 鍦嗙殑鍛ㄩ暱=鐩村緞脳鍦嗗懆鐜 s=蟺rr 鍦嗙殑闈㈢Н=鍗婂緞脳鍗婂緞脳鍦嗗懆鐜
绛旓細鍦嗙殑鍛ㄩ暱锛 c=2蟺r=蟺d 鍗婂渾鐨勫懆闀匡細c=蟺r+2r 鍦嗛潰绉細S=蟺r²鍗婂渾鐨勯潰绉細S=(蟺r²)梅2 鍦嗙幆闈㈢Н锛 S澶у渾锛峉灏忓渾=蟺(R²-r²)锛圧澶у渾鍗婂緞锛夊崐鍦嗗懆闀=蟺脳r+d 娉細鍦嗙殑鍗婂緞锛歳 鐩村緞锛歞 鍦嗗懆鐜囷細蟺锛3.1415926鈥︹︼級...
绛旓細鍦嗙殑鍗婂緞鍏紡鏄痳=d/2锛宒鏄洿寰勩傜洿寰勯氬父鐢ㄥ瓧姣嶁渄鈥濊〃绀猴紝杩炴帴鍦嗗懆涓婁袱鐐瑰苟閫氳繃鍦嗗績鐨勭洿绾跨О鍦嗙洿寰勶紝杩炴帴鐞冮潰涓婁袱鐐瑰苟閫氳繃鐞冨績鐨勭洿绾跨О鐞冪洿寰勶紝鑰屽崐寰勫氨鏄洿寰勭殑涓鍗婏紝鎵浠ュ崐寰=鐩村緞*0.5銆備笌鍦嗙浉鍏崇殑鍏紡 1銆佸崐鍦嗙殑闈㈢Н锛S鍗婂渾=(蟺r^2)/2銆傦紙r涓哄崐寰勶級銆2銆佸渾鐜潰绉細S澶у渾-S灏忓渾=蟺(R^2...
绛旓細鏂规硶 1: 宸茬煡鐩村緞璁＄畻鍦嗗崐寰锛璁＄畻鍏紡鏄細D = 2r銆傚叾涓淒鈥濅唬琛鐩村緞锛鈥渞鈥濅唬琛ㄥ崐寰勩傚叕寮忓彲鍙樻崲涓簉 = D/2銆傛柟娉 2: 宸茬煡鍛ㄩ暱姹傚崐寰锛涘懆闀垮叕寮忔槸C= 2蟺r锛屽叾涓渞鈥濅唬琛鍗婂緞锛蟺鏄渾鍛ㄧ巼锛3.14159...锛夈傛崲绠楁垚鍗婂緞鍏紡灏辨槸r = C/2蟺銆傛柟娉 3: 宸茬煡闈㈢Н璁＄畻鍗婂緞锛鍦嗙殑闈㈢НA = 蟺...
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