olemus
normeeritud ruum, mis normi abil defineeritud kauguse
\(d(x,y) = ||x - y||\) mõttes on täielik meetriline ruum
= a complete normed vector space in mathematical analysis

näiteid
= \(n\)-mõõtmeline Eukleidiline vektorruum \(\mathbb{R}^n\), milles
vektori \(x=(x_1,x_2,\ldots,x_n)\) norm
on \(||x||_p = \sqrt[p]{|x_1|^p + |x_2|^p + \ldots + |x_n|^p}\)
= seost \(\sum_i |x_i|^p<\infty\) rahuldavate
reaalarvujadade \(x=(x_0,x_1, x_2, \ldots )\)
vektorruum normiga \(||x||_p = \sqrt[p]{\sum_i |xi|^p}\)

ülevaateid
https://www.techopedia.com/definition/17852/banach-space
https://en.wikipedia.org/wiki/Banach_space
https://encyclopediaofmath.org/wiki/Banach_space
https://www.math.ucdavis.edu/~hunter/book/ch5.pdf
http://www.ma.huji.ac.il/~razk/iWeb/My_Site/Teaching_files/Banach.pdf