State the reason for cos-1[cos(-π6)]≠-π6 - Mathematics

State the reason for `cos^-1 [cos(- pi/6)] ≠ - pi/6`

Sum

We know cos(– π) = cos π

So `cos^-1 [cos( - pi/6)] = cos^-1[cos pi/6]`

= `pi/6 ≠ - pi/6`

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The Cosine Function and Inverse Cosine Function

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Chapter 4: Inverse Trigonometric Functions - Exercise 4.2 [Page 142]

Chapter 4 Inverse Trigonometric Functions
Exercise 4.2 | Q 2 | Page 142

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