Yes, I meant c>0. Thank you for clarifying!

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Hi,
How may I show that 2^(n^2)/n! converges to infinity?
 
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peripatein said:
Hi,
How may I show that 2^(n^2)/n! converges to infinity?

That is SO divergent you can afford to be pretty sloppy. 2^(n^2)/n!>2^(n^2)/n^n, right? So show 2^(n^2)/n^n diverges. Hint: look at the log.
 
Thank you, Dick!
 
Would it be correct to say that if for sequences a_n and b_n, lim a_n = infinity and |b_n|< c < infinity, then lim|a_n*b_n| = infinity?
(I think it should be correct, as we may infer that lim |bn| = c and then the limit of the product of a_n and b_n would yield c*infinity which is always infinity.)
 
peripatein said:
Would it be correct to say that if for sequences a_n and b_n, lim a_n = infinity and |b_n|< c < infinity, then lim|a_n*b_n| = infinity?
(I think it should be correct, as we may infer that lim |bn| = c and then the limit of the product of a_n and b_n would yield c*infinity which is always infinity.)

If you mean lim |b_n|=c with c>0, then sure. If c=0, then you need to think more.
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...

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