Cauchy sequence in group theory

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Recall - Cauchy sequence in analysisBefore we go into group theory, let’s recall how Cauchy sequence is defined in analysis.Real/complex numberA sequence $(x_n)_{n=1}^{\infty}$ of real/complex numbers is called a Cauchy sequence if, for every $\varepsilon>0$, there is a positive integer $N$ such tha……