巩固练习一、选择题1.若极限2220lim1hhfahfahAe,则函数fx在xa处(A)不一定可导.(B)不一定可导,但faA.(C)不一定可导,但faA(D)可导,且faA.2.设223fxxxx,则使0nf存在的最高阶数n(A)0.(B)1.(C)2.(D)3.3.设21sin,0,,0xxfxxaxbx在0x处可导,则,ab满足(A)0a,0b.(B)1a,1b.(C)a为任意常数,0b.(D)a为任意常数,1b.4.设,0,,0xxfxxx则(A)fx在0x处不连续.(B)0f存在.(C)0f不存在,曲线yfx在点0,0处不存在切线.(D)0f不存在,曲线yfx在点0,0处存在切线.二、填空题1.若函数fx在1x处的导数存在,则极限0112sin213tanlimxfxfxfxx______________.2.设01f,00f,则201coslimtanxfxx____________.3.设3232xyfx,且2arctanfxx,则0xdydx_____________.4.设2sinyx,则3dydx______________.5.设fx有任意阶导数且3fxfx,1n,则nfx_____________.6.设2ln1yx,则50y__________________.7.设21,cos,xtyt则22dydx_____________.8.曲线321xy上点5,8处的切线方程是______________.9.曲线lnyx上与直线1xy垂直的切线方程为_____________.10.曲线231,xtyt上对应点2t处的切线方程为______________.11.设函数21sin,0,0,0xxfxxx的导函数在0x处连续,则的取值为____________.三、计算题1.计算下列各题:(Ⅰ)设2sincoscos2xxyex,求dydx;(Ⅱ)设222arctantan2abxyabab,其中0ab,求y.2.设,,xftytftft其中ft三阶可导,且0ft,求ddyx,22ddyx,33ddyx;3.计算下列各题(提示,等式两边取对数后再求导):(Ⅰ)由方程yxxy确定xxy,求ddxy;(Ⅱ)方程1xyye确定yyx,求yx;4.设函数yfx有反函数xgy,且3fa,1fa,2fa,求3g.5.设函数cos,0,0gxxxfxxax其中gx二阶连续可导,且01g.(1)确定常数a,使得fx在0x处连续;(2)求...