# Concept derivation guides

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Concept guide



## [Injectivity and distinct inputs: table qualification, collision witnesses and fibers](/en/derivations/derivation-mko-injective-01/?from=%2Fen%2Fderivations%2F%3Fq%3Dmko-injective)

Let A={1,2,3,4}, B={1,2,3,4,5,6}, with function tables f: (1,4),(2,6),(3,1),(4,5); g: (1,4),(2,6),(2,6),(3,4),(4,6); h: (1,4),(2,6),(2,5),(3,1),(4,5). Decide which tables are total functions A→B; decide whether f and g are injective and list their fibers; find g's first collision in lexicographic order; decide whether g restricted to C={1,2} is injective; and treat the empty domain.

Injectivity and distinct inputs

derivation-mko-injective-01





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