Science

Math

Humanities

... and beyond

Socratic Meta
Featured Answers

Topics

Question #40e1d

1 Answer

Nov 4, 2016

#cos(pi/5+pi/20)=cos(pi/4)=root(2)2/2#

Related questions

See all questions in Sum and Difference Identities

Impact of this question

2936 views around the world

You can reuse this answer
Creative Commons License