Republic of Mathematics blog

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The value of cos(pi/5)

Posted by: Gary Ernest Davis on: December 3, 2010

@capedsam Tweeted: “Can you find an exact value for cos(pi/5)? “ x It is actually fairly easy to find an exact value for by following a path through the complex numbers. x To do this we use Euler’s identity for all real numbers . x Jim Tanton (@jamestanton) has a very nice introduction to Euler’s […]

Shoot me now! (Math jokes)

Posted by: Gary Ernest Davis on: December 2, 2010