《高等数学辅导》讲义习题讲解武忠祥练习题精选t函数/(x)=兰哭兰二.是().(A)单调函数(C)偶函数(B)周期函数/co>元界函数中国大学MOOC..)(xf1,0,1x【解】在处没定义,xxxexxxxxfxxxxxxln)1(1limln)1(1lim)(limln11111limln)1(lnlim11xxxxxxxxxxxexxxxxfxxxxxxln)1(1limln)1(1lim)(limln000111limln)1(lnlim00xxxxxxxxxxxexxxxxfxxxxxxln)1(1limln)1(1lim)(limln1112111limln)1(lnlim11xxxxxxxx,0b)(xf.0x【解】应选(C)否则只有一个间断点由题设可知,0x)(xf.1x.eb显然是的一个间断点,而另一个间断点只能是而,)(lim20eaxfx.0)(lim0xfxeexaxxfxxx12211)1)((lim)(limeexaxx112)1(lim)1(eaexaxx21212111lim)1(【解】0,01,1,2,1,0)(xxxexfx故应选(D).,0,0,10,0limxxxenxn.11,11,1,0limxxxxxnn不存在,112lim)()1(nnxxnnxeexfxnxnxnxxneeexee21)(112lim当0x时)1ln()21ln()11ln(ln222nnnnxn0x,)1ln(1xxxx【解】当时,则222222)1ln(1nknknknkknknnknknnknkxnnk1212ln21)1(21limlim212nnnnknnkn21)1(21limlim212nnnnnnknnkn21lnlimnnx.lim21exnn则)21(21limnnnn2)1(21lim2nnnn【解】)21(11lim2nnnnnnnn322210dxx【解1】nxxxnxxxeexex2)2sin1ln(02120222lim)2sin1(limnxxxxxee1lim2222)2sin1ln(02222022)2sin1ln(limnxxxxe12202)2(42sin12cos4limnxxnxxxxe02sin12coslim242202axxxnenx22,2ean222022)2sin1ln(limnxxxxe2222222022)2(sin22sin2sinlimnxxxxxxe0a242202222sinlim,2exxeanx【解2】左端222022)2sin1ln(limnxxxxe【解3】左端2222202]2sin2[]2sin)2sin1[ln(limnxxxxxxe2322202])2(61[])2(sin21[limnxxxxe)61~sin,21~)1ln((32xxxxxx2440222lim,2exxeanx.一030..确定常数a.,.b,c的值,使...