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July 25, 2014

July 25, 2014

Posted by **Kay** on Thursday, September 13, 2007 at 12:34am.

tan 7 pie/8

- Trig -
**DrRuss**, Thursday, September 13, 2007 at 8:15amtan(7pi/8) = tan(7pi/4/2)

hence

tan(7pi/8)=sin(7pi/4)/(1+cos(7pi/4))

sin(7pi/4)=-(root2)/2

cos(7pi/4)=(root2)/2

so

tan(7pi/8)= -(root2)/2/(1+(root2)/2)

and then tidy up.

Sorry about the expressions, not easy to do in text.

- Trig -
**Madi**, Thursday, March 10, 2011 at 11:40pmHow do you tidy it up?

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