设函数fx=2x-1,x<0,做出这个函数的图像 设f(x)={x-1 (x<0) , 0 (x=0) , x...
\u8bbe\u51fd\u6570 f(x)= 2x-1 x\uff1c0 x 2 -1 x\u22650 \u7684\u53cd\u51fd\u6570\u4e3af -1 \uff08x\uff09\uff0c\u5219f\u6cd5\u4e00\uff1a\u7531\u51fd\u6570 f(x)= 2x-1 x\uff1c0 x 2 -1 x\u22650 \u5f97\u5f53x\uff1c0\u65f6\uff0c x= y+1 2 \u5f53x\u22650\u65f6\uff0c x= y+1 \u7531\u6b64\u53ef\u5f97\uff1af -1 \uff08x\uff09= x+1 2 x+1 x\u2265-1 x\uff1c-1 \u6240\u4ee5f -1 \uff081\uff09= 2 \u4e3a\u6240\u6c42\uff0e\u6cd5\u4e8c\uff1a\u6839\u636e\u9898\u610f\u6c42f -1 \uff081\uff09\u7684\u503c\uff0c\u4e5f\u5c31\u662f\u6c42\u4f7ff\uff08x\uff09=1\u7684x\u503c\u2235x\uff1c0\u65f6\uff0cf\uff08x\uff09\uff1c-1\uff0cx\u22650\u65f6f\uff08x\uff09\u2265-1\u2234\u4ee4x 2 -1=1\uff0c\u5f97x= 2 \u5373f -1 \uff081\uff09= 2 \uff0e\u7b54\u6848\u4e3a\uff1a 2
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-----------\u3002------------- \u662f\u5947\u51fd\u6570\u3002
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如图
绛旓細x<=0锛宖(x)=2^x -1 x>=0锛宖(x)=-2^(-x) +1 3锛夊緢鏄剧劧锛宖(x)鏄疪涓婄殑鍗曡皟閫掑鍑芥暟 x<=0鏃讹紝f(x)=2^x -1<=f(0)=1-1=0 褰揻(x)=2^x -1>0-1=-1 鎵浠ワ細x<=0鏃讹紝-1<f(x)<=0 鏍规嵁濂囧嚱鏁版ц川鐭ラ亾锛寈>=0鏃讹紝0<=f(x)<1 鎵浠ワ細f(x)鐨勫煎煙涓猴紙-1,1锛夋晠...
绛旓細姝ら鍙互灏哫鍒嗘鏉ヨ冭檻锛屽垎X<=1/2锛1/2<X<=4锛孹>4鍘绘帀缁濆鍊硷紝鍐嶈В鏂圭▼灏卞緢绠鍗曚簡锛岃繖鏄В棰樻濊矾锛屽墿浣欑殑浣犺嚜宸卞幓鍋氬搱
绛旓細棣栧厛,鍑芥暟 f(x)=2x-1/x+1 1/x鏄噺鍑芥暟鍦(0,鈭)鎵浠-1/x鏄鍑芥暟 鎵浠(x)鏄鍑芥暟 鏈夊畠鐨勫煎煙涓(f(3),f(5))鏈澶у间负f(5)=10-1/5+1=10+4/5=54/5
绛旓細鍒欙細f(x锛1)锛峟(x)=2ax锛(a锛媌)=2x锛1锛寰楋細2a=2銆乤锛媌=锛1 a=1銆乥=锛2 寰楋細f(x)=x²锛2x锛1 f(x)=2x锛媘 x²锛4x锛1=m 璁撅細g(x)=x²锛4x锛1锛屽叾涓瓁鈭圼0锛3]浣鍑芥暟g(x)鍦ㄥ尯闂碵0锛3]涓婄殑鍥惧儚锛岃繖涓浘鍍忎笌鐩寸嚎y=m鏈変袱涓氦鐐癸紝鍒欙細m鈭(锛3锛...
绛旓細x<-1/2鏃, y=-x-5 -1/2<=x<4鏃讹紝y=3x-3 x>=4鏃,y=x-3
绛旓細(1)x鈭圼-2,-1]浠x-2|=0 |2x+1|=0 鍒 x=2 (鑸嶅幓锛,x=-1/2锛堣垗鍘伙級鏁呯涓闂畑鏃犺В 锛2锛墄鈭圼-1,0]褰 -1鈮1 鍒 -1
绛旓細骞虫柟寰4x^2+4x+1锛瀤^2-6x+9 鍗3x^2+10x-8锛0 鍗(3x-2)(x+4)锛0 瑙ｅ緱-4锛渪锛2/3 2鐢盿-3锝渪-3锝滐紲fx鎭掓垚绔 鐭-3锝渪-3锝滐紲锝2x+1锝-锝渪-3锝 鎭掓垚绔 鍗砤锛滐綔2x+1锝-锝渪-3锝+3锝渪-3锝 鎭掓垚绔 鍗砤锛滐綔2x+1锝+2锝渪-3锝 鎭掓垚绔 鍗砤锛滐綔2x+1锝+锝2x-6锝 ...
绛旓細=(x1-x2)+[(2x1+1)-(2x2+1)]/[鏍瑰彿(2x1+1)+鏍瑰彿(2x2+1)]=(x1-x2)+2(x1-x2)/[鏍瑰彿(2x1+1)+鏍瑰彿(2x2+1)]鐢变簬x1-x2>0,涓婂紡鍒嗘瘝澶т簬0 鏁呮湁:f(x1)-f(x2)>0 鏁協(x)鍦ㄥ畾涔夊煙鍐呮槸澧鍑芥暟锛(2)鐢遍掑鍑芥暟寰,褰x=-1/2鏃.鍙栧緱鏈灏忓兼槸:f(-1/2)=-1/2....
绛旓細fx=2x²-1 鏄簩娆鍑芥暟 瀵圭О杞存槸x=0 x鈭圼-1,2]鈭存渶澶у=f(2)=2*4-1=7 鏈灏忓=f(0)=2*0-1=-1 濡傛灉鎮ㄨ鍙垜鐨勫洖绛旓紝璇风偣鍑烩滈噰绾充负婊℃剰绛旀鈥,绁濆涔犺繘姝ワ紒
绛旓細f(x)=|2x+1|-|x-3|x鈮-1/2鏃讹細f(x)=-2x-1+x-3=-x-4鍗曡皟鍑忋俧(-1/2)=0-1/2-3=-7/2-1/2锛渪锛3鏃讹細f(x)=2x+1+x-3=3x-2鍗曡皟澧烇紝f(-1/2)=3*(-1/2)-2=-7/2x鈮3鏃讹細f(x)=2x+1-x+3=x+4锛屽崟璋冨鈭磞min=f(-1/2)=-7/2...
