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Which of the Following Graphs Represents a One-one Function?

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Question

Which of the following graphs represents a one-one function?

Short/Brief Note
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Solution

In the graph of (b), different elements on the x-axis have different images on the y-axis. But in (a), the graph cuts the x-axis at 3 points, which means that 3 points on the x-axis have the same image as 0 and hence, it is not one-one.
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Chapter 2: Functions - Exercise 2.5 [Page 73]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 2 Functions
Exercise 2.5 | Q 2 | Page 73

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