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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
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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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