高中數(shù)學 第三章《基本初等函數(shù)》課件2 新人教B版必修1

第二章第二章 基本初等函數(shù)基本初等函數(shù) 復(fù)習課復(fù)習課如果如果 a 0，a 1，M 0， N 0 有：有：)()()(3R)M(nnlogMlog2NlogMlogNMlog1NlogMlog(MN)loganaaaaaaa),()(Rnmaamnnm )()(Rnbaabnnn ),(Rnmaaanmnm a0,b0整數(shù)冪整數(shù)冪有理數(shù)冪有理數(shù)冪實數(shù)冪實數(shù)冪指數(shù)指數(shù)對數(shù)對數(shù)指數(shù)函數(shù)指數(shù)函數(shù)對數(shù)函數(shù)對數(shù)函數(shù)冪函數(shù)冪函數(shù)定義定義定義定義定義定義定義定義運算性質(zhì)運算性質(zhì)圖象與圖象與性質(zhì)性質(zhì)圖象與圖象與性質(zhì)性質(zhì)圖象與性質(zhì)圖象與性質(zhì)應(yīng)用應(yīng)用)1 ,1(),0,0(:1 圖象都過上上是是增增函函數(shù)數(shù)在在),0(:2 上上是是減減函函數(shù)數(shù)在在點點圖圖象象都都過過),0(:2)1 ,1(:1 時時0 ,0時時 a1 0a1 (0,+)(0,+)RR(0,1)(0,1)0y10y1y1X0X0增函數(shù)增函數(shù)減函數(shù)減函數(shù)11 a1 0a1 11(0,+)(0,+)RR(0,1)(0,1)0 x10 x1x1y0y0y0增函數(shù)增函數(shù)減函數(shù)減函數(shù) a1 a1 11RR(0,+)(0,+)(0,1)(1,0)0y1X00 x1y0增函數(shù)增函數(shù)增函數(shù)增函數(shù)課課 前前 熱熱 身身1.如圖中曲線如圖中曲線C1，C2，C3，C4分別是函數(shù)分別是函數(shù)yax，ybx，ycx，ydx的圖象，則的圖象，則a，b，c，d與與1的的大小關(guān)系是大小關(guān)系是( ) (A)ab1cd (B)ab1dc (C)ba1cd (D)ba1dc 指數(shù)函數(shù)與對數(shù)函數(shù)指數(shù)函數(shù)與對數(shù)函數(shù) 2.若圖象若圖象C1，C2，C3，C4對應(yīng)對應(yīng) y=logax, y=logbx, y=logcx, y=logdx,則（則（ ） A.0ab1cd B.0ba1dc C.0dc1ba D.0cd1a0且且a1，w則則f(x)是是( )wA.奇函數(shù)奇函數(shù) B.偶函數(shù)偶函數(shù) wC.非奇非偶函數(shù)非奇非偶函數(shù) D.奇偶性與奇偶性與a有關(guān)有關(guān)2111)(xaxf12( )0 4(log)f xfx5.已知函數(shù)的定義域為，則的定義域為2log(24).4xyx6.求函數(shù)的值域二二.函數(shù)單調(diào)性的應(yīng)用函數(shù)單調(diào)性的應(yīng)用的的大大小小比比較較例例3 .0222,3 .0log,3 .022log,2log,31log.24.1,4.1,1.1.1:531232121練練習習20.1log (62 )yxx 函數(shù)的單調(diào)增區(qū)間是：的值域的值域求函數(shù)求函數(shù)例例 8 ,21,log)2(log)(4412xxxxf換元法換元法1:( ) 422,1,1.xxf xx 練 習求的 值 域2:1.( )lg(1).f xxx 思考判斷函數(shù)的奇偶性與單調(diào)性