关于高数极限证明的几道题 证明 1.lim(xn)=n^2/(2n^3+1)=0 2.lim(3n+1)/(2n-1)=3/2 3.lim2^n/n!=0第一题中ξ=0.1,0.01,0.001时的N值要怎么求呢!

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关于高数极限证明的几道题 证明 1.lim(xn)=n^2/(2n^3+1)=0 2.lim(3n+1)/(2n-1)=3/2 3.lim2^n/n!=0第一题中ξ=0.1,0.01,0.001时的N值要怎么求呢!

关于高数极限证明的几道题 证明 1.lim(xn)=n^2/(2n^3+1)=0 2.lim(3n+1)/(2n-1)=3/2 3.lim2^n/n!=0第一题中ξ=0.1,0.01,0.001时的N值要怎么求呢!
关于高数极限证明的几道题 证明 1.lim(xn)=n^2/(2n^3+1)=0 2.lim(3n+1)/(2n-1)=3/2 3.lim2^n/n!=0
第一题中
ξ=0.1,0.01,0.001时的N值要怎么求呢!

关于高数极限证明的几道题 证明 1.lim(xn)=n^2/(2n^3+1)=0 2.lim(3n+1)/(2n-1)=3/2 3.lim2^n/n!=0第一题中ξ=0.1,0.01,0.001时的N值要怎么求呢!
1、limn^2/(2n^3 +1) =lim(1/n) / (2 + 1/n^3)
∵n→∞时,1/n→0,1/n^3 →0
所以原式=0
2、lim(3n+1)/(2n-1) = lim(3+ 1/n) / (2- 1/n) = 3/2
3、2^n/n!= 2^n/(1*2*3*...*n) < 2^n/(1*2*3*3*3...*3) = 2*(2/3)^(n-2)
所以0

证明: 1’ 当n=1时,左= (2*1-1) 2; =1, 右=1/3*1*(4*1 2’ 假设当 n=k时,命题成立 即1 2; 3 2; 5 2; (2k-1)

放缩法n^2/(2n^3+1)小于n^2/(2n^3)