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Let A = [–1, 1]. Then, discuss whether the following functions defined on A are one-one, onto or bijective: k(x) = x2 - Mathematics

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Question

Let A = [–1, 1]. Then, discuss whether the following functions defined on A are one-one, onto or bijective:

k(x) = x2 

Sum
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Solution

Given, A = [–1, 1]

Let k(x1) = k(x2)

x12 = x22

x1 = ± x2

Therefore, k(x) is not one-one.

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Chapter 1: Relations And Functions - Exercise [Page 12]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 21. (iv) | Page 12

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