어떤 급수가 각 항에 절댓값을 취한 급수가 수렴하면 절대수렴(absolute convergence)한다고 한다.
$\displaystyle{\sum _{n=1}^{\infty}|a_n|}$이 수렴하면 $\displaystyle{\sum _{n=1}^{\infty}a_n}$도 수렴하는데 이것을 절대수렴이라고 한다.
한편 $\displaystyle{\sum _{n=1}^{\infty}a_n}$도 수렴하지만 $\displaystyle{\sum _{n=1}^{\infty}|a_n|}$은 발산한다면 조건수렴(conditional convergence)이라고 한다.
https://en.wikipedia.org/wiki/Absolute_convergence
Absolute convergence - Wikipedia
From Wikipedia, the free encyclopedia Jump to navigation Jump to search Mode of convergence of an infinite series In mathematics, an infinite series of numbers is said to converge absolutely (or to be absolutely convergent) if the sum of the absolute value
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https://en.wikipedia.org/wiki/Conditional_convergence
Conditional convergence - Wikipedia
In mathematics, a series or integral is said to be conditionally convergent if it converges, but it does not converge absolutely. Definition[edit] More precisely, a series of real numbers ∑ n = 0 ∞ a n {\textstyle \sum _{n=0}^{\infty }a_{n}} is said to
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