Mathematics and Origami
We may observe that odd segments succession is a geometric progression with ratio 1 / 2. Same
happens with even segments.
Let ́s calculate the ratio of any two consecutive terms:
2
2
2 1
2
2
1
=
−
−
=
AB
BC
2
2
2
2
2
1
2
= = =
BC
AB
BC
CD
2
2
2
= =
CD
BC
CD
DE
2
2
2
= =
DE
CD
DE
EF
Therefore,
2
2
r=
Let ́s figure out the sum of all the terms of this progression. Applying formula (1) and bearing
in mind that an → 0, we have:
( )
2
1
2
2
2 1
1
(^1) =
−
− −
−
−
r
a
S
Which shows that such sum has equal value than the square`s diagonal, as it should be.
Interlude