हिंदी

(A) F ( X ) = Sin 2 X , G ( X ) = √ X (B) F ( X ) = Sin X , G ( X ) = | X | (C) F ( X ) = X 2 , G ( X ) = Sin √ X F and G Cannot Be Determined.

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प्रश्न

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

 

विकल्प

  •  \[f\left( x \right) = \sin^2 x, g\left( x \right) = \sqrt{x}\]

  • \[f\left( x \right) = \sin x, g\left( x \right) = |x|\]

  • \[f\left( x \right) = x^2 , g\left( x \right) = \sin \sqrt{x}\]

  •  f and g cannot be determied

MCQ
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उत्तर

If we solve it  by the trial-and-error method, we can see that (a) satisfies the given condition.
From (a):

\[f\left( x \right) = \sin^2 x \text{ and } g\left( x \right) = \sqrt{x}\] 
\[ \Rightarrow f\left( g\left( x \right) \right) = f\left( \sqrt{x} \right) = \sin^2 \sqrt{x} = \left( \sin \sqrt{x} \right)^2\]

So, the answer is (a).

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अध्याय 2: Functions - Exercise 2.6 [पृष्ठ ७७]

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आर.डी. शर्मा Mathematics Volume 1 and 2 [English] Class 12
अध्याय 2 Functions
Exercise 2.6 | Q 32 | पृष्ठ ७७

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