RESULTS ON THE COMPOSITION AND NEUTRIX COMPOSITION OF THE DELTA FUNCTION

Brian Fisher, Biljana Jolevska–Tuneska
617 363

Öz


The neutrix composition F (f (x))) of a distribution F (x) and a locallysummable function f (x) is said to exist and be equal to the distributionh(x) if the neutrix limit of the sequence {Fn (f (x))} is equal to h(x),where Fn (x) = F (x) ∗ δn (x) and {δn (x)} is a certain sequence of infinitely differentiable functions converging to the Dirac delta-functionδ(x). It is proved that the neutrix composition δ(s) {[exp + (x) − 1]r } exists andδ (s) {[exp + (x) − 1]r } = rs+r−1k=0 (−1)s+k s!c rs+r−1,k2rk! δ (k) (x), for r = 1, 2, . . . and s = 0, 1, 2, . . .. Further results are also proved.

Anahtar kelimeler


distribution, dirac-delta function, composition of distributions, neutrix,neutrix limit.

Referanslar


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