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If F ( X ) = Sin 2 X and the Composite Function G ( F ( X ) ) = | Sin X | Then G(X) is Equal to (A) √ X − 1 (B) √ X (C) √ X + 1 (D) − √ X

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Question

If  \[f\left( x \right) = \sin^2 x\] and the composite function   \[g\left( f\left( x \right) \right) = \left| \sin x \right|\] then g(x) is equal to

Options

  • \[\sqrt{x - 1}\]

  • \[\sqrt{x}\]

  • \[\sqrt{x + 1}\]

  • \[- \sqrt{x}\]

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Solution

(b) \[\text{If we takeg}\left( x \right) = \sqrt{x}, \text{then}\] 
\[g\left( f\left( x \right) \right) = g\left( \sin^2 x \right) = \sqrt{\sin^2 x} = \pm \sin x = \left| \sin x \right|\]

So, the answer is (b).

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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 46 | Page 79

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