要函数y=3^x的图像。
\u753b\u51fa\u51fd\u6570y=-x+3\u7684\u56fe\u50cf
\u4e0a\u73ed\u65f6\u95f4\u5077\u5077\u753b\u7684\uff0c\u54c8\u54c8\u3002\u8981\u91c7\u7eb3\u54e6
\u7b54\uff1a1\uff09
y=[(3-x)/(3+x)]*e^x\u7684\u56fe\u50cf\u89c1\u4e0b\u56fe\uff1a
f(x)<0\u7684\u89e3\u96c6\u4e3a\uff1a(-\u221e\uff0c-3\uff09\u222a\uff083\uff0c+\u221e\uff09
2\uff09
y=a^x/(a^x+\u221aa)
=1/[1+a^(1/2-x)]
\u56fe\u50cf\u6052\u8fc7\u70b9\uff081/2\uff0c1/2\uff09
\u56fe\u50cf\u4ee5a=0.5\u548ca=2\u4e3a\u4f8b\u89c1\u56fe
0<a<1\uff0c\u662fR\u4e0a\u7684\u51cf\u51fd\u6570\uff0c\u503c\u57df\u4e3a\uff080,1\uff09
a>1\uff0c\u662fR\u4e0a\u589e\u51fd\u6570\uff0c\u503c\u57df\u4e3a\uff080,1\uff09
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绛旓細1. y=x^3鐨勫浘鍍鏄竴鏉＄粡杩囧師鐐(0,0)鐨勬洸绾裤2. 鎵╁睍璧勬枡锛氳鐢诲嚭y=x^3鐨勫浘鍍忥紝棣栧厛闇瑕佺‘瀹氬叾瀹氫箟鍩熷拰鍊煎煙銆3. 鍏舵锛屽垽鏂瓂=x^3鐨勫鍋舵э紝鐢变簬瀵逛簬浠讳綍x鍊硷紝閮芥湁x^3 = (-x)^3锛屽洜姝よ鍑芥暟鏄鍑芥暟銆4. 鎺ヤ笅鏉ワ紝姹傚嚭y=x^3鐨勬瀬闄愶紝褰搙瓒嬪悜浜庢鏃犵┓鎴栬礋鏃犵┓鏃讹紝y涔熻秼鍚戜簬姝ｆ棤绌枫
绛旓細x+y=1 (x+y)^2=1 x^2+2xy+y^2=1 x^3+y^3=1/3 (x+y)(x^2-xy+y^2)=1/3 x^2-xy+y^2=1/3 涓ゅ紡鐩稿噺锛3xy=2/3 xy=2/9 鏍规嵁闊﹁揪瀹氱悊鍒楁柟绋嬶細a^2-a+2/9=0 9a^2-9a+2=0 (3a-1)(3a-2)=0 a1=1/3,a2=2/3 x=1/3,y=2/3鎴杧=2/3,y=1/3 x^5+...
绛旓細y=x^3鐨勫浘鍍鏄竴鏉＄粡杩囧師鐐(0,0)鐨勬洸绾裤
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绛旓細y=x^(2/3)鍥惧儚濡備笅锛氫竴鑸湴锛寉=x^伪锛埼变负鏈夌悊鏁帮級鐨勫嚱鏁帮紝鍗充互搴曟暟涓鸿嚜鍙橀噺锛屽箓涓哄洜鍙橀噺锛屾寚鏁颁负甯告暟鐨勫嚱鏁扮О涓哄箓鍑芥暟銆備緥濡鍑芥暟y=x^0 銆亂=x^1銆亂=x^2銆亂=x^-1锛堟敞锛歽=x^-1=1/x銆亂=x^0鏃秞鈮0锛夌瓑閮芥槸骞傚嚱鏁般
绛旓細搴旇鏄敾鍑y=3^x鐨勫嚱鏁板浘鍍鍜寉=x^2-1鐨勫浘鍍锛屾壘涓や釜鍥惧儚鐨勪氦鐐瑰惂銆
