Golden ratio

There are 16 NRICH Mathematical resources connected to Golden ratio
Gold Yet Again
problem

Gold Yet Again

Age
16 to 18
Challenge level
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Nick Lord says "This problem encapsulates for me the best features of the NRICH collection."
Golden Fractions
problem

Golden Fractions

Age
16 to 18
Challenge level
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Find the link between a sequence of continued fractions and the ratio of succesive Fibonacci numbers.
Golden Fibs
problem

Golden Fibs

Age
16 to 18
Challenge level
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When is a Fibonacci sequence also a geometric sequence? When the ratio of successive terms is the golden ratio!
Pentakite
problem

Pentakite

Age
14 to 18
Challenge level
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Given a regular pentagon, can you find the distance between two non-adjacent vertices?
Golden Ratio
problem

Golden Ratio

Age
16 to 18
Challenge level
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Solve an equation involving the Golden Ratio phi where the unknown occurs as a power of phi.
Pent
problem

Pent

Age
14 to 18
Challenge level
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The diagram shows a regular pentagon with sides of unit length. Find all the angles in the diagram. Prove that the quadrilateral shown in red is a rhombus.
Golden Powers
problem

Golden Powers

Age
16 to 18
Challenge level
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You add 1 to the golden ratio to get its square. How do you find higher powers?
Darts and Kites
problem

Darts and Kites

Age
14 to 16
Challenge level
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Explore the geometry of these dart and kite shapes!
Golden Triangle
problem

Golden Triangle

Age
16 to 18
Challenge level
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Three triangles ABC, CBD and ABD (where D is a point on AC) are all isosceles. Find all the angles. Prove that the ratio of AB to BC is equal to the golden ratio.
Pythagorean Golden Means
problem

Pythagorean Golden Means

Age
16 to 18
Challenge level
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Show that the arithmetic mean, geometric mean and harmonic mean of a and b can be the lengths of the sides of a right-angles triangle if and only if a = bx^3, where x is the Golden Ratio.