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Write the Value of Cos - Mathematics

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Question

Write the value of cos \[\left( 2 \sin^{- 1} \frac{1}{2} \right)\]

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Solution

We have, cos \[\left( 2 \sin^{- 1} \frac{1}{2} \right)\]

= \[\cos\left( 2 \times \frac{\pi}{6} \right) = \cos\left( \frac{\pi}{3} \right) = \frac{1}{2}\]

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Chapter 4: Inverse Trigonometric Functions - Exercise 4.15 [Page 117]

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RD Sharma Mathematics [English] Class 12
Chapter 4 Inverse Trigonometric Functions
Exercise 4.15 | Q 20 | Page 117

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