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Find the General Solution of the Following Equation: Cos 3 X = 1 2

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Question

Find the general solution of the following equation:

\[\cos 3x = \frac{1}{2}\]
Sum
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Solution

We have:

\[\cos3x = \frac{1}{2}\]

⇒ \[\cos3x = \cos \frac{\pi}{3}\]

⇒ \[3x = 2n\pi \pm \frac{\pi}{3}\]

\[n \in Z\]

⇒ \[x = \frac{2n\pi}{3} \pm \frac{\pi}{9}\]

\[n \in Z\]
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Chapter 11: Trigonometric equations - Exercise 11.1 [Page 21]

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R.D. Sharma Mathematics [English] Class 11
Chapter 11 Trigonometric equations
Exercise 11.1 | Q 2.02 | Page 21

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