(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

Find the exact value of:

sin (-5∏/12)

2. The attempt at a solution

sin (-45° + -30°) =

sin -45° cos -30° + cos -45° sin -30° =

(sqrt (2) / 2 )(sqrt (3) / 2 ) + (sqrt (2) / 2)(1 / 2) =

(sqrt (6) + sqrt (2)) / 4

However, the book has (-sqrt (6) - sqrt (2)) / 4 as the answer.

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# Homework Help: Problem needing trig identities to find exact value

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