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Find the value of the following: tan-1 [2 cos (2 sin-1 1/2)] - Mathematics

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Question

Find the value of the following:

`tan^-1 [2 cos (2  sin^-1  1/2)]`

Sum
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Solution

Let `sin^-1  1/2` = x

⇒ sin x = `1/2`

⇒ `sin (pi/6)`

⇒ `sin^-1  1/2 = pi/6`

∴ `tan^-1 [2  cos (2 sin^-1  1/2)]`

= `tan^-1 [2  cos (2 xx pi/6)]`

= `tan^-1 [2  cos (pi/3)]`

= `tan^-1 [2  xx 1/2]`

= tan−1 (1)

= `pi/4`

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Chapter 2: Inverse Trigonometric Functions - Exercise 2.2 [Page 48]

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NCERT Mathematics Part 1 and 2 [English] Class 12
Chapter 2 Inverse Trigonometric Functions
Exercise 2.2 | Q 11 | Page 48

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