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If F : R → R Be Defined by F(X) = (3 − X3)1/3, Then Find Fof (X).

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Question

If f : R → R be defined by f(x) = (3 − x3)1/3, then find fof (x).

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Solution

  \[\left( fof \right) \left( x \right) = f \left( f \left( x \right) \right)\]
\[ = f \left( \left( 3 - x^3 \right)^\frac{1}{3} \right)\]
\[ = \left[ 3 - \left( \left( 3 - x^3 \right)^\frac{1}{3} \right)^3 \right]^\frac{1}{3} \]
\[ = \left[ 3 - \left( 3 - x^3 \right) \right]^\frac{1}{3} \]
\[ = \left( x^3 \right)^\frac{1}{3} \]
\[ = x\]
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Chapter 2: Functions - Exercise 2.5 [Page 74]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 2 Functions
Exercise 2.5 | Q 34 | Page 74

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