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September 22, 2014

September 22, 2014

Posted by **Anonymous** on Tuesday, November 13, 2012 at 2:06pm.

- math -
**Steve**, Tuesday, November 13, 2012 at 2:28pmluckily, you have nice easy 3-4-5 and 5-12-13 triangles.

cosx = -4/5

siny = 5/13

sin(x+y) = (3/5)(-12/13) + (-4/5)(5/13) = -56/65

reasonable, since (x+y) will be in QIII or QIV

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