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Question
Let f: R → R be the function defined by f(x) = 4x – 3 ∀ x ∈ R. Then write f–1
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Solution
Given that f(x) = 4x – 3 = y (say), then
4x = y + 3
⇒ x = `(y + 3)/4`
Hence f–1(y) = `(y + 3)/4`
⇒ f–1(x) = `(x + 3)/4`
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