抛物线顶点式公式是什么 谁知道 抛物线顶点式的公式
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(1)\u56fe\u8c61\u4e0ey\u8f74\u4e00\u5b9a\u76f8\u4ea4\uff0c\u4ea4\u70b9\u5750\u6807\u4e3a(0\uff0cc)\uff1b
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(1)\u5f53\u9898\u7ed9\u6761\u4ef6\u4e3a\u5df2\u77e5\u56fe\u8c61\u7ecf\u8fc7\u4e09\u4e2a\u5df2\u77e5\u70b9\u6216\u5df2\u77e5x\u3001y\u7684\u4e09\u5bf9\u5bf9\u5e94\u503c\u65f6\uff0c\u53ef\u8bbe\u89e3\u6790\u5f0f\u4e3a\u4e00\u822c\u5f62\u5f0f\uff1a
y=ax2+bx+c(a\u22600)\u3002
(2)\u5f53\u9898\u7ed9\u6761\u4ef6\u4e3a\u5df2\u77e5\u56fe\u8c61\u7684\u9876\u70b9\u5750\u6807\u6216\u5bf9\u79f0\u8f74\u65f6\uff0c\u53ef\u8bbe\u89e3\u6790\u5f0f\u4e3a\u9876\u70b9\u5f0f\uff1ay=a(x-h)²+k(a\u22600)\u3002
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\u4e00\u822c\u5f62\u5f0f\u662fy=ax^2+bx+c \u5199\u6210\u9876\u70b9\u5f0f\u662fy=a(x+b/2a)^2+(4ac-b^2)/4a
y=ax²+bx+c（a≠0）的顶点坐标公式是（-b/2a，（4ac-b²）/4a) y=ax²+bx的顶点坐标是（-b/2a，-b²/4a)b/-2a 4ac-b2/4a
横坐标：-b/2a 纵坐标(4ac-b^2)/4ac
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绛旓細骞朵笖瀹冪殑鍥惧儚杩樺叿鏈夐潪甯稿鐨勭壒娈婃с2銆佷唬鏁版帹鐞 浼楁墍鍛ㄧ煡锛屼簩娆″嚱鏁扮殑鍑芥暟寮忔槸y = ax2 + bx + c锛岃瀵熷叾鍑芥暟寮忛潪甯哥殑绠鍗曪紝鑰屼笌鍏跺搴旂殑鎶涚墿绾鍥惧儚鍗存瘮杈冨鏄撳彂鐢熷彉褰紝渚嬪锛屽湪鍏朵腑浼氭湁涓鑸紡銆椤剁偣寮浠ュ強闆剁偣寮忕瓑绛夛紝鍥犳锛屽湪瑙ｅ喅浜屾鍑芥暟闂鐨勮繃绋嬩腑锛屽叾鍑芥暟寮忎細寰楀埌闈炲父骞挎硾鐨勫簲鐢ㄣ
