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प्रश्न
Give an example of a map which is neither one-one nor onto
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उत्तर
Let f: R → R, be a mapping defined by f(x) = x2
Then clearly f(x) is not one-one as f(1) = f(–1).
Also range of f(x) is `[0, oo)`.
Therefore, f(x) is neither one-one nor onto.
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