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Is the following relation a function? Justify your answer R2 = {(x, |x |) | x is a real number} - Mathematics

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Question

Is the following relation a function? Justify your answer

R2 = {(x, |x |) | x is a real number}

Sum
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Solution

R2 = {(x, |x |) / x ∈R}

For every x ∈ R there will be unique image as |x | ∈ R.

Therefore R2 is a function.

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Chapter 2: Relations and Functions - Solved Examples [Page 24]

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NCERT Exemplar Mathematics [English] Class 11
Chapter 2 Relations and Functions
Solved Examples | Q 5.(ii) | Page 24

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