计算lim(n→∞)(1^n+2^n+3^n)^(1/n)

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计算lim(n→∞)(1^n+2^n+3^n)^(1/n)计算lim(n→∞)(1^n+2^n+3^n)^(1/n)计算lim(n→∞)(1^n+2^n+3^n)^(1/n)3=(3^n)^(1/n)

计算lim(n→∞)(1^n+2^n+3^n)^(1/n)
计算lim(n→∞)(1^n+2^n+3^n)^(1/n)

计算lim(n→∞)(1^n+2^n+3^n)^(1/n)
3=(3^n)^(1/n)<=(1^n+2^n+3^n)^(1/n)<=(3*3^n)^(1/n)
lim(n→∞)3=3=)<=lim(n→∞)3(3)^(1/n)=3
由挟逼准则知
lim(n→∞)(1^n+2^n+3^n)^(1/n)=3

3^n<1^n+2^n+3^n<3*3^n
3^n<1^n+2^n+3^n<3^(n+1)
lim(n→∞)(1^n+2^n+3^n)^(1/n)=3