790e9d90-3532-11eb-a37e-e580c0970d9b2022考研数学零基础提前学作业3(答案）考研资料.pdfVIP免费

2022全程班零基础提前学作业答案2新浪微博@考研数学周洋鑫12022年一笑而过全程班“提前学”课程作业答案同步作业3考点3七种未定式极限计算【1】011limcotsintanxxxx→−解析：300costansintansinlimlimsinsintanxxxxxxxxxxx→→−−=()()()33333333001111362limlim2xxxxoxxxoxxoxxx→→++−−++===.【2】求极限222cos40eelimxxxx−→−.解析：()2222cos2cos222cos4400ee1eelimlimxxxxxxxxx−+−−→→−−=3243300012cos2sin16limlimlim2212xxxxxxxxxxx→→→+−−====.【3】cos230eelim11xxx→−=+−．解析：原式cos1320e(1e)lim11xxx−→−=+−02e(1cos)lim13xxx→−=2021e2lim13xxx→=3e2=．【4】201tan1sinlim1sinxxxxxx→+−++−解析：()10221tan1sinlim1sin1xxxxx→+−++−2022全程班零基础提前学作业答案2新浪微博@考研数学周洋鑫2()02tansinlim1sin1tan1sin2xxxxxxx→−=+++（有理化）()()33330311136lim122xxxoxxxoxx→++−−+=（非零因子）()32031112lim1222xxoxx→+==.【5】()()01coslim1cosln12xxxx+→−−+解析：()()()()22001cos1cos1coslimlim11cos22xxxxxxxxx++→→−+−=+()()2220011cos12limlim1cos1os4cxxxxxxxx++→→−===++【6】若011lime1xxaxx→−−=，则a等于.解析：原式00111elimeelim11xxxxxaaaxxx→→−=−+=+=−+=所以2a=．故选C．【7】2limarctanxxx→+解析：2222212arctan121limlim2112limarctan1lim1.xxxxxxxxxxxxeeeee→+→+→+→+−+−−−−+====【8】()tan2limsinxxx→解析：原式()2limtansin1xxxe→−=2022全程班零基础提前学作业答案2新浪微博@考研数学周洋鑫3()2sinsin1limcosxxxxe→−=2sin1limcosxxxe→−=（非零因子）2coslimsin01xxxee→−===.【9】()10lim,,03xxxxxabcabc→++解析：0013lim1lim33xxxxxxxxabcabcxxee→→++++−−=0lnlnlnlnlnln1limln3333xxxxaabbccabcabceeeabc→++++====.【10】21limln1xxxx→−+解析：令1xt=，则()222001ln112limlim2ttttttt→→−+==.【11】011lim().1exxxx−→+−−解析：200111elim()lim1e(1e)xxxxxxxxxx−−−→→++−+−=−−2201elimxxxxx−→+−+=0012e2e3limlim.222xxxxxx−−...