苏教二次函数的图像和性质学到什么程度 二次函数的图像和性质是初中数学吗
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_______
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y=ax^2+K (0\uff0cK) x=0
y=a(x-h)^2 (h\uff0c0) x=h
y=a(x-h)^2+k (h\uff0ck) x=h
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y=ax^2+bx+c(a\u22600)\uff0e
(2)\u5f53\u9898\u7ed9\u6761\u4ef6\u4e3a\u5df2\u77e5\u56fe\u8c61\u7684\u9876\u70b9\u5750\u6807\u6216\u5bf9\u79f0\u8f74\u6216\u6781\u5927\uff08\u5c0f\uff09\u503c\u65f6\uff0c\u53ef\u8bbe\u89e3\u6790\u5f0f\u4e3a\u9876\u70b9\u5f0f\uff1ay=a(x-h)^2+k(a\u22600)\uff0e
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\u53c2\u89c1\uff1ahttp://zhidao.baidu.com/question/290706009.html
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013年11月1日在增城二中进行了《二次函数2yaxk的图象与性质》
两节全市公开课，听完这两节课，给予我们备课组很大的启发。
两位老师都能做到让学生尽可能多地动手，给学生充足的空间，让学生们自主交流、展示成果、互相质疑，积极鼓励学生参与课堂教学，让学生成为课堂的主体。香江中学的黄布发老师发挥教师的个人魅力，激发学生的学习欲望，课堂气氛活跃，让学生对数学充满兴趣，也让数学课堂充满活力，真正地把课堂还给学生。这是非常值得我们学习的地方。
从这两节课当中，我们知道，要做到有效的课堂教学，就应该有效备课，备好学生；教学手段要多样化，多想办法降低学生的学习难度，提高了学生的学习效率；我们要突出教师有效的引导作用，学生才是课堂教学的主体。
绛旓細10. 浜屾鍑芥暟鐨勬ц川锛氫簩娆″嚱鏁扮殑鍥惧儚鍏锋湁瀵圭О鎬с佽酱瀵圭О鎬у拰鍛ㄦ湡鎬銆備簡瑙ｈ繖浜涙ц川鍙互甯姪鎴戜滑鏇村揩鍦拌В鍐冲疄闄呴棶棰樸傞氳繃浠ヤ笂鐭ヨ瘑鐐圭殑瀛︿範鍜岀悊瑙ｏ紝浣犲彲浠ユ洿濂藉湴鎺屾彙浜屾鍑芥暟鐨勬湰璐ㄥ拰瑙ｉ鎶宸с傚笇鏈涜繖浜涘唴瀹硅兘瀵逛綘鏈夋墍甯姪锛
绛旓細浜ょ偣寮忥細y=a(x-x1)(x-x2) [浠呴檺浜庝笌x杞存湁浜ょ偣A锛坸1,0锛夊拰 B锛坸2,0锛夌殑鎶涚墿绾縘娉細鍦3绉嶅舰寮忕殑浜掔浉杞寲涓,鏈夊涓嬪叧绯:h=-b/2a k=(4ac-b²)/4a x1,x2=(-b卤鈭歜²-4ac)/2a 浜屻浜屾鍑芥暟鐨勫浘璞 鍦ㄥ钩闈㈢洿瑙掑潗鏍囩郴涓綔鍑轰簩娆″嚱鏁皔=x²鐨勫浘璞,鍙互鐪嬪嚭,浜屾鍑...
绛旓細浜屾鍑芥暟鐨勫浘鍍忎笌鎬ц川浠嬬粛濡備笅锛氫簩娆″嚱鏁板浘璞℃槸鎶涚墿绾匡紝鏄酱瀵圭О鎬у浘褰銆倅=ax鐨勫浘璞℃槸鏈绠鍗曠殑浜屾鍥惧儚锛屽涔犱篃杈冨鏄撱傞《鐐瑰潗鏍囦负锛0锛0锛夛紝鍗冲師鐐癸紱瀵圭О杞翠负y杞达紝寮鍙ｇ敱a鐨勬璐熷喅瀹氥備竴鑸紡锛歽=ax^2+bx+c锛坅鈮0锛宎銆乥銆乧涓哄父鏁帮級甯告暟椤筩鍐冲畾鎶涚墿绾夸笌y杞翠氦鐐广備簩娆″嚱鏁版渶楂樻蹇呴』涓轰簩娆★紝...
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绛旓細2銆佷簩娆″嚱鏁扮殑鍥惧儚锛氱煡璇嗚鐐 1銆佽鐞嗚В鍑芥暟鐨勬剰涔夈2銆佽璁颁綇鍑芥暟鐨勫嚑涓〃杈惧舰寮忥紝娉ㄦ剰鍖哄垎銆3銆佷竴鑸紡锛岄《鐐瑰紡锛屼氦鐐瑰紡锛岀瓑锛屽尯鍒嗗绉拌酱锛岄《鐐癸紝鍥惧儚锛寉闅忕潃x鐨勫澶ц屽噺灏忥紙澧炲ぇ锛夛紙澧炲噺鍊硷級绛夌殑宸紓鎬с4銆佽仈绯诲疄闄呭鍑芥暟鍥惧儚鐨勭悊瑙ｃ5銆佽绠楁椂锛岀湅鍥惧儚鏃跺垏璁板彇鍊艰寖鍥淬6銆侀殢鍥惧儚鐞嗚В鏁板瓧鐨勫彉鍖...
绛旓細浜屾鍑芥暟 浜屾鍑芥暟涓庡渾鐨勭煡璇嗕竴鏍凤紝鍦ㄥ垵涓暟瀛﹀崰鏈夐噸瑕佺殑鍦颁綅.瀵逛簩娆″嚱鏁扮殑鑰冩煡缁忓父璺熸柟绋嬬瓑鐭ヨ瘑鐩哥粨鍚.姒傚康涓庡浘鍍 閲嶇偣闅剧偣 (1)鑳藉鏍规嵁瀹為檯闂锛岀啛缁冨湴鍒楀嚭浜屾鍑芥暟鍏崇郴寮忥紝骞舵眰鍑哄嚱鏁扮殑鑷彉閲忕殑鍙栧艰寖鍥.(2)鐞嗚В鎶涚墿绾跨殑鏈夊叧姒傚康锛屼細鐢ㄦ弿鐐规硶鐢诲嚭浜屾鍑芥暟y=ax2鐨勫浘璞,鎺㈢储鎺屾彙浜屾鍑芥暟鐨勬ц川....
绛旓細1銆佷簩娆″嚱鏁扮殑鎬ц川锛氱壒鍒湴锛屼簩娆″嚱鏁帮紙浠ヤ笅绉板嚱鏁帮級y=ax2+bx+c(a鈮0)锛屽綋y=0鏃讹紝浜屾鍑芥暟涓哄叧浜巟鐨勪竴鍏冧簩娆℃柟绋嬶紙浠ヤ笅绉版柟绋嬶級锛屽嵆ax2+bx+c=0(a鈮0)姝ゆ椂锛屽嚱鏁鍥惧儚涓x杞存湁鏃犱氦鐐瑰嵆鏂圭▼鏈夋棤瀹炴暟鏍广傚嚱鏁颁笌x杞翠氦鐐圭殑妯潗鏍囧嵆涓烘柟绋嬬殑鏍广2銆浜屾鍑芥暟鐨勫浘鍍锛...
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绛旓細III.浜屾鍑芥暟鐨勫浘鍍 鍦ㄥ钩闈㈢洿瑙掑潗鏍囩郴涓綔鍑轰簩娆″嚱鏁皔=x^2鐨勫浘鍍,鍙互鐪嬪嚭,浜屾鍑芥暟鐨勫浘鍍忔槸涓鏉℃姏鐗╃嚎銆 IV.鎶涚墿绾跨殑鎬ц川 1.鎶涚墿绾挎槸杞村绉板浘褰傚绉拌酱涓虹洿绾 x = -b/2a銆 瀵圭О杞翠笌鎶涚墿绾垮敮涓鐨勪氦鐐逛负鎶涚墿绾跨殑椤剁偣P銆傜壒鍒湴,褰揵=0鏃,鎶涚墿绾跨殑瀵圭О杞存槸y杞(鍗崇洿绾縳=0) 2.鎶涚墿绾挎湁涓涓《鐐筆,鍧愭爣涓:...
