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1:28 PM
This question was closed for lack of context, now it has 3 reopen votes:
1
Q: Why $\alpha\le L_1$ for any $L_1>L$ implies $\alpha\le L$?

AAAAAAAFirst part Second part Let $\alpha=\limsup|s_n|^{1/n}$ and $L=\limsup\left|\frac{s_{n+1}}{s_n}\right|$. We need to prove $\alpha\le L$. This is obvious if $L=+\infty$, so we assume $L<+\infty$. To prove $\alpha\le L$ it suffices to show $$\alpha\le L_1 \qquad\text{for any}\qquad L_1>L.$$ ...

Now I found this question:
2
Q: Proving a lim sup inequality in Chapter 12 of Kenneth Ross's "Elementary Analysis"

user84815I am struggling to digest and understand Theorem 12.2 (p. 76) in Elementary Analysis: The Theory of Calculus by Kenneth Ross Theorem 12.2 Let $s_n$ be any sequence of nonzero real numbers. Then we have lim sup $\mid$$s_n$$\mid$$^($$^1$$^/$$^n$$^)$ $\leq$ lim sup $\mid$$s_n$$_+$$_1...

I would say that they are duplicates.
 
 
2 hours later…
2:59 PM
1
Q: Prove that $\limsup _{n\to \infty}(a_n+b_n)\leq \limsup _{n\to \infty}a_n + \limsup _{n\to \infty}b_n$

JohanLiebertLet $(a_n)$ and $b_n$ be bounded sequences of real numbers. Prove that $$\limsup _{n\to \infty}(a_n+b_n)\leq \limsup _{n\to \infty}a_n + \limsup _{n\to \infty}b_n$$ How can this be proved? Using the definition of limit, can I use the fact that $\sup|a_n + b_n|\leq \sup|a_n| + \sup|b_n|$?

6
Q: Prove $\limsup\limits_{n \to \infty} (a_n+b_n) \le \limsup\limits_{n \to \infty} a_n + \limsup\limits_{n \to \infty} b_n$

hyg17I am stuck with the following problem. Prove that $$\limsup_{n \to \infty} (a_n+b_n) \le \limsup_{n \to \infty} a_n + \limsup_{n \to \infty} b_n$$ I was thinking of using the triangle inequality saying $$|a_n + b_n| \le |a_n| + |b_n|$$ but the problem is not about absolute values of the seq...

1
Q: How to prove these inequalities: $\liminf(a_n + b_n) \leq \liminf(a_n) + \limsup(b_n) \leq \limsup(a_n + b_n)$

ymfoiThe inequalities are: $$\liminf(a_n + b_n) \leq \liminf(a_n) + \limsup(b_n) \leq \limsup(a_n + b_n)$$

3
Q: Subadditivity of the limit superior

Thomas$$ \limsup \left(f(h)+g(h)\right) \leq \limsup f(h)+ \limsup g(h).$$ How can we prove this? Any help would be appreciated.

These questions look to be the same (or at least very similar).
Maybe the last one from the above questions is slightly different, since it (probably) is not about sequences. (The OP did not clarify this even after beoing asked in the comment.)
This one is also about limsup in reals:
1
Q: Prove two inequalities about limit inferior and limit superior

Scorpio19891119I wish to prove the following two inequalities: Suppose $X$ is a subset in $\Bbb R$, and functions $f$ and $g$: $X\to \Bbb R$, and $x_{0}\in X$ is a limit point. Then: $$\lim\sup_{x\to x_0}(f(x)+g(x))\le \lim\sup_{x\to x_0}(f(x))+\lim\sup_{x\to x_0}(g(x))$$ and,$$\lim\inf_{x\to x_0}(f(x))+\...

Probably at least some of the above questions should be closed as duplicates.
I have cast some close votes on some of them. Feel free to vote in some other direction if you prefer.
 

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