Which of the following is a one-one (injective) function from ℝ to ℝ?
Solution
f(x) = x³ is strictly monotonic (always increasing) → one-one. f(x) = x² is not one-one (f(1)=f(-1)=1); |x| also not; sin x not (periodicity).
About this question
Subject: Mathematics · Chapter: Sets, Relations and Functions · Topic: Types of Functions
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