班级:学号:姓名:日期:月号1第二章导数与微分1.判断题(1)错(2)对(3)对(4)错(5)对(6)错(7)错(8)对(9)对(10)对2选择题(1)D(2)A(3)A(4)B(5)C(6)B(7)A(8)B(9)D(10)C3填空题(1)1.(2)3.(3)11lndlnxyyxyyyxxxxxy−−−−.(4)55−.(5)2yx=−+,322(1)t−−.(6)34π.(7)17−.(8)100!.(9)2!nn,1(2)(1)!nnn−−+,2(1)!nn−.(10)22cos3xx,sinx−.4.解:(0)0()()ffxfx==−−,两边对x求导'()'()()'()'(0)1fxyfxyfyf+=∀⇒==,()fxx⇒=5.解:设切点为00,xy(),则00000log11lnayxyxxa⎧⎪=⎪⎪=⎨⎪⎪=⎪⎩001exyeae==⎧⎪⇒⎨⎪=⎩.6.解:切线方程为1(1)ynx=+−1111lim()lim(1)nnnynneξξ→∞→∞⇒=−⇒=−=.7.解:2ddddcos32,sincos0dddd1sinxxxxyxxxettetetttttet=+−⋅−=⇒=−,当0t=时1dd2,ddyxett−==,故切线方程为2(1)yex=+.8.(1)0α>,(2)1α>,(3)2α>导函数连续,(4)3α>.9.解:222222d()ddddddddd,ddddddddddtttttdyetyytyytyydteeeexxtxtxtxtt−−−−−==⋅=⋅=⋅=−,故原方程为222dd-53ddtyyett=.10.解:2222231d(.)d1d1dd11dsindcos.dcosdcosddcosdcosdcosddytyyyytytdtxtxttttttttt==⋅==+⋅故原方程为22d-30dyyt=.11.(1)解:方程两边同时求n阶导数:2(2)(1)()(1)()(1)2(1)220nnnnnxynxynnyxyny++++++−++=令0x=,则(2)()(0)(1)(0)nnynny+=−+,由(0)(0)0'(0)1yy⎧=⎪⎨=⎪⎩,可得()02(0)(1)(2)!21nknkyknk=⎧=⎨−=+⎩(2)解:arcsinyx=满足方程2(1-)"'0xyxy−=,两边两边同时求n阶导数,得:班级:学号:姓名:日期:月号22(2)(1)()(1)()(2)2()1-2(1)0(0)(0)nnnnnnnxynxynnyxynyyny++++−−−−−=⇒=().由(0)(0)0'(0)1yy==,,得()202(0)((2-1)!!)21nnkyknk=⎧=⎨=+⎩.12.证明:(1)直接求导可得证;(2)在(xdyaxb+=+)两边同时求n阶导数,得:(1)()(1)()(0nnnncnxdycnyyycxd++++=⇒=−+),由(1),可得证.13.证明:(1)若()()fxfx=−,则'()'()fxfx=−−.(2)同理.(3)若()()fxfxl=+,则'()'()fxfxl=+.14.解:由已知'()(0)()fxfxox=+,故'22'22111()(0)()1()(0)()ffonnnnnffonnn⎧=+⎪⎪⎨⎪⎪=+⎩�⇒211=lim'(0)'(0)2nnffn→∞+=�原式.15.解(1)错(2)对(用反证法证明)(3)错(4)错反例如下:(1)与(3)00010(),()01000xxxxxxxφϕ≠≠⎧⎧===⎨⎨==⎩⎩;0()(4)0()||xxxxxφϕ===.16.解:211()121xxabfxxaxbx⎧>⎪++⎪==⎨⎪⎪+<⎩,则1()1=12()=abfxababfxa++⇒=+⇒+=⇒连续可导2,故212,1'()2121xxabfxxx>⎧⎪==−==⎨⎪<⎩.17.解:2d2d332d22d2232d1dd1d(sin)0dd1()()dddddd.ddddsin0()ddyxyxxyyxyxyyyxxxdxxyyyxdyyxxx=⇒−++=⎛⎞⎜⎟−⎜⎟⎝⎠==⇒−−=原式为.18.解:1,1,02abc≠−==时()fx具有一阶连续导数,但在0x=不存在二阶导数.19.解:(1)0axb−,(2)bae.20.解:(1)'(0)aϕ=,(2)'()fx在点0x=处连续.