圆的半径公式 圆的半径公式
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\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\uff0co\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
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\u5706\u7684\u534a\u5f84\u516c\u5f0f\uff1a
C=2\u03c0r\uff0c\u5f97\u5230r=C/2\u03c0
S=\u03c0r^2\uff0cr=\u6839\u53f7\u4e0bs/\u03c0
V=(4/3)\u03c0r^3\uff0c \u5f97\u5230r=\u4e09\u6b21\u6839\u53f7\u4e0b(3v)/ (4 \u03c0)
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r=C÷π÷2
C=2πr（c周长，π圆周率，r半径）所以r=C/2πd=2r（d直径）所以r=d/2s=πr²（s面积）所以r=√s/π（r>0）
绛旓細鍦嗙殑鍗婂緞鍏紡锛欳=2蟺r锛屽緱鍒皉=C/2蟺 S=蟺r^2锛宺=鏍瑰彿涓媠/蟺 V=(4/3)蟺r^3锛屽緱鍒皉=涓夋鏍瑰彿涓(3v)/(4蟺)銆
绛旓細鍦嗙殑鍗婂緞鍏紡锛歳=1/2鈭氾紙D²+E²-4F锛銆傚渾鐨勪竴鑸柟绋嬫槸锛歺²+y²+Dx+Ey+F=0(D²+E²-4F>0)锛屽叾涓渾蹇冨潗鏍囨槸锛-D/2锛-E/2锛夈傛墖褰㈠姬闀縇=鍦嗗績瑙掞紙寮у害鍒讹級脳R= n蟺R/180锛埼镐负鍦嗗績瑙掞級锛圧涓烘墖褰㈠崐寰勶級鎵囧舰闈㈢НS=n蟺 R²/360=LR/2锛圠涓...
绛旓細鍦嗙殑鍗婂緞鍏紡锛歳=1/2鈭氾紙D²+E²-4F锛銆傚渾鐨勪竴鑸柟绋嬫槸x²+y²+Dx+Ey+F=0(D²+E²-4F>0)锛屽叾涓渾蹇冨潗鏍囨槸锛-D/2锛-E/2锛夈傚埄鐢ㄥ渾鐨勫懆闀垮叕寮忔眰鍗婂緞锛宺=C/2蟺銆傚埄鐢ㄥ渾鐨勯潰绉叕寮忔眰鍗婂緞锛宺=鈭氾紙S/蟺锛夈傚湪鍚屼竴骞抽潰鍐咃紝鍒板畾鐐圭殑璺濈绛変簬瀹氶暱鐨勭偣鐨...
绛旓細鍦嗙殑鍗婂緞鍏紡鏄痳=d/2銆傚崐寰勫叕寮忎负锛歳=d/2锛宒鏄洿寰勩傜洿寰勬槸鎸囬氳繃涓骞抽潰鎴栫珛浣撳浘褰腑蹇冨埌杈逛笂涓ょ偣闂寸殑璺濈锛岄氬父鐢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鐞冪洿寰勩傝屽崐寰勫氨鏄洿寰勭殑涓鍗婏紝鎵浠ュ崐寰=鐩村緞*0.5銆傚渾鐨勬ц川锛1銆佸渾鏄酱瀵圭О鍥惧舰锛...
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锛歋鍗婂渾=(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...
绛旓細梅4 R=(H²+L²梅4)梅2H=H/2+L²/8H 鍦嗘垨鍦嗙殑鍗婂緞鏄粠鍏朵腑蹇冨埌鍏跺懆杈圭殑浠讳綍绾挎锛屽苟涓斿湪鐜颁唬鐨勪娇鐢ㄤ腑锛屽畠涔熸槸鍏朵腑浠讳綍涓涓殑闀垮害銆傚崐寰勭殑澶嶆暟鍙互鏄崐寰勶紙鎷変竵鏂囧鏁帮級鎴栧父瑙勮嫳鏂囧鏁板崐寰勩傚崐寰勭殑鍏稿瀷缂╁啓鍜屾暟瀛﹀彉閲忓悕绉颁负r銆 閫氳繃寤朵几锛岀洿寰刣瀹氫箟涓哄崐寰勭殑涓ゅ嶏細d=2r銆
绛旓細鍦嗙殑鍗婂緞鍏紡锛r=1/2鈭锛圖²+E²-4F锛夈傛湁鍏冲渾鐨勮绠楀叕寮忥細1銆佸渾鐨勫懆闀緾=2蟺r=蟺d銆2銆佸渾鐨勯潰绉疭=蟺r²銆3銆佹墖褰㈠姬闀縧=n蟺r/180銆4銆佹墖褰㈤潰绉疭=n蟺r²锛360=rl/2銆5銆佸渾閿ヤ晶闈㈢НS=蟺rl銆傚渾鐨勬ц川 1銆佸渾鏄酱瀵圭О鍥惧舰锛屽叾瀵圭О杞存槸浠绘剰涓鏉￠氳繃鍦嗗績鐨勭洿绾裤傚渾...
绛旓細鍦嗙殑鍗婂緞鍏紡锛欳=2蟺r锛屽緱鍒皉=C/2蟺 S=蟺r^2锛宺=鏍瑰彿涓媠/蟺 V=(4/3)蟺r^3锛 寰楀埌r=涓夋鏍瑰彿涓(3v)/ (4 蟺)
绛旓細鍦嗙殑涓鑸柟绋鍗婂緞涓猴細r=鈭氾紙D+E-4F锛夛紡2锛屽埄鐢ㄥ渾鐨勫懆闀鍏紡姹傚崐寰勶紝r=C/2蟺锛屽埄鐢ㄥ渾鐨勯潰绉叕寮忔眰鍗婂緞锛宺=鈭氾紙S/蟺锛夈傛湁鍏冲渾鐨勮绠楀叕寮 1銆佸渾鐨勫懆闀緾=2蟺r=蟺d 2銆佸渾鐨勯潰绉疭=蟺r²3銆佹墖褰㈠姬闀縧=n蟺r/180 4銆佹墖褰㈤潰绉疭=n蟺r²锛360=rl/2 5銆佸渾閿ヤ晶闈㈢НS=蟺rl 鍦嗙殑...
绛旓細鍦嗗崐寰勭殑璁＄畻鍏紡鏄痳=1/2鈭锛圖²+E²-4F锛夛紝鍦ㄥ彜鍏稿嚑浣曚腑锛屽渾鎴栧渾鐨勫崐寰勬槸浠庡叾涓績鍒板叾鍛ㄨ竟鐨勪换浣曠嚎娈碉紝骞朵笖鍦ㄦ洿鐜颁唬鐨勪娇鐢ㄤ腑锛屽畠涔熸槸鍏朵腑浠讳綍涓涓殑闀垮害銆傚崐寰勭殑澶嶆暟鍙互鏄崐寰勶紙鎷変竵鏂囧鏁帮級鎴栧父瑙勮嫳鏂囧鏁板崐寰勩傚崐寰勭殑鍏稿瀷缂╁啓鍜屾暟瀛﹀彉閲忓悕绉颁负r銆傞氳繃寤朵几锛岀洿寰刣瀹氫箟涓哄崐寰勭殑涓ゅ嶃
