NCERT Example 11 - Relations and Functions
Question: Decide whether each relation is a function: (i) {(2,1),(3,1),(4,2)}; (ii) {(2,2),(2,4),(3,3),(4,4)}; (iii) {(1,2),(2,3),(3,4),(4,5),(5,6),(6,7)}.
Answer: (i) and (iii) are functions; (ii) is not a function.
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