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Find the value of sin 690°.

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Question

Find the value of sin 690°.

Sum
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Solution

sin 690° = sin (720° – 30°)

= sin (2 × 360° – 30°)

= – sin 30°

= `- 1/2`

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Chapter 3: Trigonometry - 2 - Exercise 3.2 [Page 42]

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