- direct sum
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Math.a composition of two disjoint sets, as vector spaces, such that every element in the composition can be written uniquely as the sum of two elements, one from each of the given sets.[1925-30]
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Universalium. 2010.
direct sum
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direct sum — noun a union of two disjoint sets in which every element is the sum of an element from each of the disjoint sets (Freq. 1) • Hypernyms: ↑union, ↑sum, ↑join * * * noun : cartesian product herein * * * Math. a composi … Useful english dictionary
direct sum — noun Date: circa 1928 Cartesian product compare direct product … New Collegiate Dictionary
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Direct product of groups — Concepts in group theory category of groups subgroups, normal subgroups group homomorphisms, kernel, image, quotient direct product, direct sum semidirect product, wreath product … Wikipedia
