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September 20, 2014

September 20, 2014

Posted by **jim** on Monday, January 2, 2012 at 6:44pm.

cos 9 pi

cos 13pi/2

sin(-17 pi0

are all of these undefined?

- pre calc -
**Damon**, Monday, January 2, 2012 at 7:15pmsin 20 pi = sin (2 pi*10) = sin 2pi = 0

cos 9 pi = cos (8 pi +pi). That is 4 times around the circle plus pi so it is really cos (pi) = -1

No, they are not undefined.

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