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Let f(x)=x3 be a function with domain {0, 1, 2, 3}. Then domain of f−1 is ______.

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Question

Let \[f\left(x\right) = x^3\] be a function with domain {0, 1, 2, 3}. Then domain of \[f^{-1}\] is ______.

Options

  • {3, 2, 1, 0}

  • {0, −1, −2, −3}

  • {0, 1, 8, 27}

  • {0, −1, −8, −27}

MCQ
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Solution

Let f(x) = x3 be a function with domain {0, 1, 2, 3}. Then domain of f-1 is {0, 1, 8, 27}.

Explanation:

f(x) = x3

Domain = {0, 1, 2, 3}

Range = {03, 13, 23, 33} = {0, 1, 8, 27}

So, f = {(0, 0), (1, 1), (2, 8), (3, 27)}

f-1 = {(0, 0), (1, 1), (8, 2), (27, 3)}

Domain of f-1 = {0, 1, 8, 27}

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Chapter 2: Functions - Exercise 2.6 [Page 79]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 2 Functions
Exercise 2.6 | Q 48 | Page 79

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