• 2022-06-16
    证明f(x)=3^n/n!当n趋于无穷时limf(x)=0.
  • 根据斯特林公式,n!=[根号(2pin)][(n/e)^n][e^(t/12n)]其中01,所以f(x)<3^n/[(n/e)^n]=[3e/n]^n又f(x)>0,[3e/n]^n-->0所以00

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