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Question

Let $\langle x_n \rangle$ be a sequence which is given by $x_n = \frac{5^n}{n!}$, then

The correct answer is
$\langle x_n \rangle$ is convergent.

Sequence Limit Analysis

The sequence $\langle x_n \rangle$ is defined by $x_n = \frac{5^n}{n!}$. To determine its behavior, we evaluate its limit as $n$ approaches infinity.

Ratio Calculation for Convergence

Consider the ratio of consecutive terms:

$ \frac{x_{n+1}}{x_n} = \frac{5^{n+1}}{(n+1)!} \times \frac{n!}{5^n} $

Simplifying this expression gives:

$ \frac{x_{n+1}}{x_n} = \frac{5^{n+1}}{5^n} \times \frac{n!}{(n+1)!} = 5 \times \frac{1}{n+1} = \frac{5}{n+1} $

Now, we calculate the limit of this ratio:

$ L = \lim_{n \to \infty} \frac{x_{n+1}}{x_n} = \lim_{n \to \infty} \frac{5}{n+1} = 0 $

Convergence Determination

A limit $L < 1$ for the ratio of consecutive terms typically implies convergence towards 0. More directly, it's a known mathematical result that for any real number $a$, the limit $\lim_{n \to \infty} \frac{a^n}{n!} = 0$. Applying this with $a=5$:

$ \lim_{n \to \infty} x_n = \lim_{n \to \infty} \frac{5^n}{n!} = 0 $

Since the limit exists and is a finite real number (0), the sequence $\langle x_n \rangle$ is convergent.

Final Conclusion

The sequence $\langle x_n \rangle$ converges to 0.

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Important Questions from Mixed Topic (CUET PG)

  1. Who was the founder of Bolshevik Communist party?
  2. What is the key guide to statecraft in the realist tradition?
  3. Chronologically arrange the events in the Cold War period.
    A. Berlin Wall is constructed
    B. Communist China joins the UN
    C. Soviet invasion of Czechoslovakia
    D. Berlin Blockade
    Choose the correct answer from the options given below:
  4. Morgenthau's principles of political realism are:
    A. Politics is rooted in permanent and unchanging human nature which is basically self centred, self-regarding and self-interested
    B. Politics is an autonomous sphere of action and cannot therefore be reduced to morals
    C. International Politics is an arena of conflicting self-interests
    D. The ethics of international relations is situational ethics which is very different from private morality
    Choose the correct answer from the options given below:

  5. Who among the following political thinkers consider the anarchical self help system to be a compelling factor for States to maximise their relative power positions?

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