（1）抛物线y=x^2-2x的顶点坐标为
\u629b\u7269\u7ebfy=x\u00d7x+2x+1\u7684\u9876\u70b9\u5750\u6807\u662f\uff1f\u9876\u70b9\u5750\u6807\u662f\uff08-1,0\uff09
\u5bf9\u4e8ey=aX^2+bX+c
\u9876\u70b9\u5750\u6807\u4e3a\uff1a\uff08-b/2a\uff0c(4ac-b^2)/4a\uff09
\u8c22\u8c22\uff0c\u4f60\u5f88\u597d\u5b66\uff0c\u5475\u5475
\u6c42\u9876\u70b9\u5750\u6807\u6709\u4e24\u79cd\u89e3\u6cd5\u3002
1\u3001\u7528\u516c\u5f0f\u6cd5\u3002\u9876\u70b9\u5750\u6807\u7684\u6a2a\u5750\u6807\u4e3a(-b/2a\uff09\u3002\u7eb5\u5750\u6807\u4e3a\uff084ac-b^2\uff09/\uff084a\uff09
2\u3001\u5316\u6210\u9876\u70b9\u5f0f\u3002\u8fd9\u91cc\u5316\u6210\u4e4b\u540e\u4e3a\uff1ay=\uff08x-1\uff09²\u3002\u5750\u6807\u4e3a\uff081\uff0c0\uff09
y=x^2-2x=(x-1)^2-1
(1,-1)
（2）若抛物线y=x^2+bx+c顶点的横坐标是-3，且过点（-1，0），则b=_6_,c=__5__
(3)将两个方程联立:a-b+3=0,25a+5b+3=0,求a,b
25b-75+5b+3=0
30b=72
b=2.4
a=-0.6
(1) (1,-1)
(2) b=6 c=5
(3) a=-0.6 b=2.4
1) (1,-1)
(2) b=6 c=5
(3) a=-0.6 b=2.4
绛旓細鍙堝洜涓,x1+x2=-b/a=2 ,x1x2=c/a=m,閭ｄ箞 锛坸2-x1锛塣2 = x1^2+ x2^2 -2x1x2 =(x1+x2)^2 -4x1x2 =4-4m 浠ｅ叆鍒颁笂闈㈠紡瀛,鏈 (m-1)^2=(1/4)*(4-4m)鍖栨垚涓鍏冧簩娆℃柟绋,鏈 锛坢-1)^2 + (m-1)=0 m*(m-1)=0 m=0鎴栬卪=1 鍙堝洜涓烘湁涓や釜浜ょ偣,鎵浠x^2-2...
绛旓細鏄剧劧瀵逛簬x灞炰笌R锛寉鐨勬渶灏忓间负x=1鏃讹紝 y=-1;1) 褰 t+1 <= 1鏃讹紝鍗 t<=0鏃讹紝x = t+1鏃, y鍙栧緱鏈灏忓硷細t^2 -1 2) 褰搕>=1鏃讹紝x = t 鏃讹紝y鍙栧緱鏈灏忓硷細 t^2 - 2t 3) 褰搕<1,涓 1<t+1鏃讹紝 鍗 0<t<1 鏃讹紝x = 1 鏃讹紝 y鍙栧緱鏈灏忓硷細 -1....
绛旓細y'=2x-2 浠=2,寰梱'=2脳2-2=2,鍒囩嚎鏂滅巼涓2,娉曠嚎涓庡垏绾垮瀭鐩,鏂滅巼浜掍负璐熷掓暟,娉曠嚎鏂滅巼=-1/2 鍒囩嚎鏂圭▼锛歽-2=2(x-2),鏁寸悊,寰y=2x-2 娉曠嚎鏂圭▼锛歽-2=(-1/2)(x-2),鏁寸悊,寰梱=-x/2 +3
绛旓細y=x^2-2x+2 =x^2-2x+1+1 =(x-1)^2+1 鎵浠ラ《鐐锛1锛1锛閫堿
绛旓細(1)鏄撴眰鐐笴(1,-3),A(1-鈭3),B(1+鈭3),鈻矨BC涓虹瓑杈逛笁瑙掑舰,鍏朵腑蹇冨嵆澶栨帴鍦嗗渾蹇僊(1,-2).鍗婂緞闀夸负2.(2)鍥犫柍ABC涓虹瓑杈逛笁瑙掑舰鏁呭姡寮B鎵瀵圭殑鍦嗗績瑙掍负120掳.鏁呭姡寮B=4蟺/3.(3)璁鎶涚墿绾涓Y杞翠氦鐐逛负D.鍒橠(0.-2),鏄剧劧鏈墊OD|=2=|MC|,OD鈭C,鍒欏洓杈瑰舰CMOD涓哄钩琛屽洓杈瑰舰,OC鍜孧D...
绛旓細璁剧洿绾y=kx-1涓巠杞翠氦浜嶥锛0锛-1锛锛屽垯SCPQ=SCDQ+SCDP锛屽洜涓簓杞村钩鍒嗕笁瑙掑舰CPQ鐨勯潰绉紝鎵浠 SCDQ=SCDP锛岃 SCDQ=1/2*|CD|*|xQ|锛孲CDP=1/2*|CD|*|xP|锛屾墍浠銆丵鐨勬í鍧愭爣xP涓巟Q浜掍负鐩稿弽鏁般傚皢 y=kx-1 浠ｅ叆鎶涚墿绾寰 kx-1=x^2-2x-3锛屽寲绠寰 x^2-(k+2)x-2=0锛岀敱闊﹁揪瀹氱悊...
绛旓細y=x^2-2x+2鍙互鍖栫畝涓猴細y=x^2-2x+1+1=(x-1)^2+1 杩欐牱鍙互鐪嬪嚭锛屽綋x=1鏃跺欙紝y=1,褰搙涓嶄负1鏃讹紝y鐨勫煎氨浼氬鍔狅紝杩欐槸涓涓紑鍙ｅ悜涓婄殑鎶涚墿绾 鏈浣庣偣鍧愭爣灏辨槸锛锛1,1锛
绛旓細瑙ｏ細锛1锛浠=0,x^2-2mx+m^2-9=0,鎵浠モ柍=锛-2m锛塣2-4m^2+36>0,鎵浠ユ棤璁簃涓轰綍鍊兼椂锛屾柟绋媥^2-2mx+m^2-9=0锛岃缁嗘濊矾鍜岀瓟妗堝湪杩欏摝http://qiujieda.com/exercise/math/798856鍦ㄥ钩闈㈢洿瑙掑潗鏍囩郴xOy涓紝宸茬煡鎶涚墿绾縴=x^2-2mx+m^2-9.(1)姹傝瘉锛氭棤璁簃涓轰綍鍊硷紝璇ユ姏鐗╃嚎涓巟杞存绘湁...
绛旓細鎬诲緱鏉ヨ锛屽埄鐢ㄧ殑闊﹁揪瀹氱悊 鍜岄厤鏂规硶 璁 Y=X^2-2X +c 锛坈<0 ) 婊¤冻棰樻剰 锛岃 A(x1,0) B ( x2,0 ) 锛岄《鐐逛负 锛1锛宑-1锛鐢遍煢杈惧畾鐞嗭細 x1+ x2=2 锛寈1 x2 = c 褰 tan瑙扨AB=2 鏃讹紝寰楋細 1-c = ( x1-x2 ) 鐨勭粷瀵瑰 涓よ竟骞虫柟骞跺皢绛夊彿鍙宠竟閰嶆柟 锛 1 -2c...
绛旓細锛1锛鐢卞绉拌酱寰楋細x=-b/2a=-1 瑙ｅ緱a=1 鎶涚墿绾涓巟杞翠氦浜庣偣A锛-3,0锛変唬鍏ュ緱,c=-3 鎵浠ユ姏鐗╃嚎涓:y=x^2+2x-3 鎵浠ュ綋x=0鏃,y=-3,鍗崇偣C锛0,-3锛夊皢A锛-3,0锛,鐐笴锛0,-3锛夌敤寰呭畾绯绘暟娉曟眰瑙 寰楃洿绾緼C涓:y=x-3 锛2锛夊綋y=0鏃,x^2+2x-3=0 瑙ｅ緱x=-3鎴杧=1 鎵浠锛1...
