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Question
Let the function f: R → R be defined by f(x) = 4x – 1, ∀ x ∈ R. Then, show that f is one-one.
Solution
For any two elements x1 , x2 ∈ R such that f(x1) = f(x2),
We have 4x1 – 1 = 4x2 – 1
⇒ 4x1 = 4x2
i.e., x1 = x2
Hence f is one-one.
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