Golden ratio

The golden ratio, $\varphi$, is the irrational algebraic number $$\varphi = \dfrac{1+\sqrt{5}}{2}.$$

Properties

Limit of quotient of consecutive Fibonacci numbers
Relationship between sine, imaginary number, logarithm, and the golden ratio
Relationship between cosine, imaginary number, logarithm, and the golden ratio

Videos

The Golden Ratio & Fibonacci Numbers: Fact versus Fiction

References

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