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If f(x) = (4 – (x – 7)3}, then f–1(x) = ______. - Mathematics

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Question

If f(x) = (4 – (x – 7)3}, then f–1(x) = ______.

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Solution

If f(x) = (4 – (x – 7)3}, then f–1(x) = `7 + (4 - x)^(1/3)`.

Explanation:

Given that, f(x) = [4 – (x – 7)3]

Let y = [4 – (x – 7)3]

⇒ (x – 7)3) = 4 – y

⇒ (x – 7) = `(4 - y)^(1/3)`

⇒ x = 7 + `(4 - y)^(1/3)`

⇒ f–1(x) = `7 + (4 - x)^(1/3)`

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Chapter 1: Relations And Functions - Exercise [Page 17]

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NCERT Exemplar Mathematics [English] Class 12
Chapter 1 Relations And Functions
Exercise | Q 52 | Page 17

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