Consider a rectangular piece of paper whose respective length and width are 5√2 and 5.

Use paper folding alone to find the value of tan 22.5^o.

I previously showed how to subdivide a length into any number of equal lengths.

Doing this we can create a strip of width 1.

Then bisect a corner this strip to get a 45º angle and then mountain fold to bisect again for a 22.5º angle. 

A triangle is formed with legs 1 and tan 22.5º

Posted by Jer on 2014-09-06 00:24:51