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If f: R → R be given by f(x) = (3 – x^3)^(1/3), then fof(x) is ______.

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Question

If f: R → R be given by `f(x) = (3 - x^3)^(1/3)`, then fof(x) is ______.

Options

  • `1/(x^3)`

  • x3

  • x

  • (3 – x3)

MCQ
Fill in the Blanks
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Solution

x

Explanation:

f: R → R is given as `f(x) = (3 - x^3)^(1/3)`

`f(x) = (3 - x^3)^(1/3)`

∴ fof(x) = f(f(x))

= `f((3 - x^3)^(1/3))`

= `[3 - ((3 - x^3)^(1/3))^3]^(1/3)`

= `[3 - (3 - x^3)]^(1/3)`

= `(x^3)^(1/3)`

= x

∴ fof(x) = x

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