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Give an example of a map which is one-one but not onto

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प्रश्न

Give an example of a map which is one-one but not onto

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उत्तर

Let f: N → N, be a mapping defined by f(x) = x2

For f(x1) = f (x2)

Then, `x_1^2 = x_2^2`

x1 = x2  ......(Since x1 + x= 0 is not possible)

Further ‘f’ is not onto, as for 1 ∈ N, there does not exist any x in N such that f(x) = 2x + 1.

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अध्याय 1: Relations And Functions - Exercise [पृष्ठ १२]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
अध्याय 1 Relations And Functions
Exercise | Q 19. (i) | पृष्ठ १२

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