2. What is the golden ratio?
ο Two quantities are in the golden ratio if their ratio is the
same as the ratio of their sum to the larger of the two
quantities.
3. Exact value of phi(Ο) and its properties
ο Ο = (β5 + 1) / 2 β 1.618
ο Ο = 1 / Ο or Ο * Ο = 1
ο Ο = (β5 - 1) / 2 β 0.618
ο Ο2 = 1 + Ο ( x2 β x β 1 = 0, the positive root is Ο)
7. Recursive property one
ο All triangles are similar.
ο The ratio between the corresponding sides of any triangle
and the next smaller triangle is Ο.
23. Proof of recursive property three
An + A n π
2
+ A n π
4
+ β― + A n π
2π
ππ π ππππ π‘π πππππππ‘π¦
π΄ π β
1
1 β
1
π2
By using geometric series, the above expression becomes: