圆的方程式是什么?
\u5706\u7684\u4e00\u822c\u65b9\u7a0b\u5f0f\u662f\u4ec0\u4e48\u6837\u7684\u5706\u5fc3(a,b)\uff0c\u534a\u5f84r (x-a) +(y-b) =r \u9762\u79efS=\u03c0R2 \u5468\u957f C=2\u03c0R\u4f60\u662f\u8981\u95ee\u8fd9\u4e2a\u5417\uff1f X^2+Y^2=1 \u88ab\u79f0\u4e3a1\u5355\u4f4d\u5706 x^2+y^2=r^
圆心(a,b),半径r(x-a)²+(y-b)²=r²
X^2+Y^2=1 被称为1单位圆 x^2+y^2=r^2,圆心O(0,0),半径r; (x-a)^2+(y-b)^2=r^2,圆心O(a,b),半径r x^2+y^2+Dx+Ey+F=0
设半径为R,圆心为(m,n),则|m|=|n|=根[R^2-(4/2)^2]=根(R^2-4),即m=n=-根(R^2-4).而圆心在x+y+6=0,故[-根(R^2-4)]+[-根(R^2-4)]+6=0 <==> R^2=13;m=n=-根(13-4)=-3。因此,圆方程为(x+3)^2+(y+3)^2=13。
面积 S=πR2
周长 C=2πR
你是要问这个吗?
绛旓細鍦嗙殑涓鑸柟绋嬩负锛歺2+y2+Dx+Ey+F=0 (D2+E2-4F>0)锛屾垨鍙互琛ㄧず涓(X+D/2)2+(Y+E/2)2=(D2+E2-4F)/4銆傚渾鐨勬ц川锛1銆佸渾鏄畾鐐圭殑璺濈绛変簬瀹氶暱鐨勭偣鐨勯泦鍚堛2銆佸渾鐨勫唴閮ㄥ彲浠ョ湅浣滄槸鍦嗗績鐨勮窛绂诲皬浜庡崐寰勭殑鐐圭殑闆嗗悎銆3銆佸渾鐨勫閮ㄥ彲浠ョ湅浣滄槸鍦嗗績鐨勮窛绂诲ぇ浜庡崐寰勭殑鐐圭殑闆嗗悎銆4銆佸悓鍦嗘垨绛夊渾鐨...
绛旓細鍦嗙殑鏂圭▼寮忥細鍦嗙殑鏍囧噯寮忔槸 锛坸-a锛塣2+锛坹-b锛塣2=r^2 鍦嗙殑涓鑸紡鏄 x^2+y^2+D*x+E*y+F=0 锛 瑕佹弧瓒 D^2+E^2+4*F > 0锛夛紝鎴栧彲浠ヨ〃绀轰负(X+D/2)2+(Y+E/2)2=(D2+E2-4F)/4銆傚渾鐨勬爣鍑嗘柟绋(x-a)²+(y-b)²=r²涓紝鏈変笁涓弬鏁癮銆乥銆乺锛屽嵆鍦嗗績...
绛旓細鍦嗙殑鏍囧噯寮忔槸 锛坸-a锛塣2+锛坹-b锛塣2=r^2鍦嗙殑涓鑸紡鏄 x^2+y^2+D*x+E*y+F=0 锛 瑕佹弧瓒 D^2+E^2+4*F > 0锛夊渾鐨勫弬鏁版柟绋嬶細 x=a+Rsin0 y=b+Rcos0 (0涓哄弬鏁帮級鍦嗙殑鏋佸潗鏍囨柟绋嬶細 璁 鍦嗗績M(蟻',胃') 鍗婂緞r 鏋佺偣O 鍦嗕笂浠绘剰涓鐐筆(蟻,胃)螖OPM涓 鐢变綑寮﹀畾鐞 ...
绛旓細鍦嗘柟绋锛 (x+2)²+(y-1)²=5
绛旓細鍦嗙殑鏂圭▼寮忛氬父涓 (x - a)^2 + (y - b)^2 = r^2锛屽叾涓 (a, b) 鏄渾蹇冪殑鍧愭爣锛宺 鏄崐寰勩傚渾鐨勬柟绋嬪紡鏄暟瀛︿腑鐢ㄦ潵鎻忚堪骞抽潰涓婁竴涓渾鐨勬暟瀛﹁〃杈惧紡銆傛渶甯歌鐨勫渾鐨勬柟绋嬪紡褰㈠紡鏄 (x - a)^2 + (y - b)^2 = r^2锛岃繖閲 (a, b) 琛ㄧず鍦嗗績鐨勫潗鏍囷紝r 琛ㄧず鍦嗙殑鍗婂緞銆傝繖涓柟绋嬪紡琛ㄨ揪鐨...
绛旓細鍦嗙殑涓鑸鏂圭▼鏄x²+y²+Dx+Ey+F=0(D²+E²-4F>0)鍏朵腑鍦嗗績鍧愭爣鏄細锛-D/2锛-E/2锛夈傚崐寰勶細1/2鈭氾紙D²+E²-4F锛夈傚渾鐨勪竴鑸柟绋嬶紝鏄暟瀛﹂鍩熺殑鐭ヨ瘑銆傚渾鐨勪竴鑸柟绋嬩负 x²+y²+Dx+Ey+F=0 (D²+E²-4F>0)锛屾垨鍙互琛ㄧず涓(X...
绛旓細1銆佹爣鍑鏂圭▼锛(x锛峚)²锛(y锛峛)²=R²锛屽渾蹇(a锛宐)鍗婂緞R锛2銆佷竴鑸柟绋嬶細x²锛媦²锛婦x锛婨y锛婩=0锛屽叾涓璂²锛婨²锛岶>0锛3銆佸弬鏁版柟绋嬶細x=a锛婻cos胃锛寉=b锛婻sin胃锛屽渾蹇(a锛宐)鍗婂緞R锛屽叾涓0鈮の<2蟺銆
绛旓細鍦嗙殑涓鑸鏂圭▼鏄x²+y²+Dx+Ey+F=0(D²+E²-4F>0)锛屽叾涓渾蹇冨潗鏍囨槸锛-D/2,-E/2锛夛紝鍗婂緞 銆愭牴鍙凤紙D²+E²-4F锛夈/2銆
绛旓細鍦嗙殑鏍囧噯寮忔槸 锛坸-a锛塣2+锛坹-b锛塣2=r^2鍦嗙殑涓鑸紡鏄 x^2+y^2+D*x+E*y+F=0 锛堣婊¤冻 D^2+E^2+4*F > 0锛夊渾鐨勫弬鏁版柟绋嬶細x=a+Rsin0 y=b+Rcos0 (0涓哄弬鏁帮級鍦嗙殑鏋佸潗鏍囨柟绋嬶細璁 鍦嗗績M(蟻',胃')鍗婂緞r 鏋佺偣O 鍦嗕笂浠绘剰涓鐐筆(蟻,胃)螖OPM涓 鐢变綑寮﹀畾鐞 |OM|^2+|OP|...
绛旓細鍦嗙殑鏍囧噯鏂圭▼灏辨槸锛坸- a锛²+锛坹- b锛²=r²銆傚渾鐨勬爣鍑鏂圭▼寮忔槸鎻忚堪涓涓渾鍦ㄥ钩闈㈠潗鏍囩郴涓殑琛ㄧず鏂规硶鐨勯噸瑕佸伐鍏枫傝鍦嗗績涓猴紙a锛宐锛夛紝鍗婂緞涓簉锛岄偅涔堝渾鐨勬爣鍑嗘柟绋嬪氨鏄紙x- a锛²+锛坹- b锛²=r²銆傝繖涓柟绋嬪紡鐨勬帹瀵煎熀浜庡渾鐨勫熀鏈ц川锛氬渾蹇冨埌鍦嗕笂浠绘剰涓鐐圭殑...