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July 24, 2014

July 24, 2014

Posted by **Cody** on Friday, February 18, 2011 at 5:00pm.

- trig -
**Reiny**, Friday, February 18, 2011 at 5:22pmthen cosx = -1/√3

x must be in II or III

in II:

sinx = √2/√3

sin 2x = 2sinxcosx = 2(√2/√3)(-1/√3) = -2√2/3

in III:

sinx = -√2/√3

sin 2x = +2√2/3

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