Iteration

There are 23 NRICH Mathematical resources connected to Iteration
A Very Shiny Nose?
problem

A Very Shiny Nose?

Age
16 to 18
Challenge level
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This problem explores the biology behind Rudolph's glowing red nose, and introduces the real life phenomena of bacterial quorum sensing.
Archimedes Numerical Roots
problem

Archimedes Numerical Roots

Age
16 to 18
Challenge level
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How did Archimedes calculate the lengths of the sides of the polygons which needed him to be able to calculate square roots?
Difference Dynamics
problem

Difference Dynamics

Age
14 to 18
Challenge level
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Take three whole numbers. The differences between them give you three new numbers. Find the differences between the new numbers and keep repeating this. What happens?
Ford Circles
problem

Ford Circles

Age
16 to 18
Challenge level
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Can you find the link between these beautiful circle patterns and Farey Sequences?
Peaches in General
problem

Peaches in General

Age
14 to 16
Challenge level
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It's like 'Peaches Today, Peaches Tomorrow' but interestingly generalized.
Spirostars
problem

Spirostars

Age
16 to 18
Challenge level
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A spiropath is a sequence of connected line segments end to end taking different directions. The same spiropath is iterated. When does it cycle and when does it go on indefinitely?
Stretching Fractions
problem

Stretching Fractions

Age
14 to 16
Challenge level
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Imagine a strip with a mark somewhere along it. Fold it in the middle so that the bottom reaches back to the top. Stetch it out to match the original length. Now where's the mark?
Slippage
problem

Slippage

Age
14 to 16
Challenge level
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A ladder 3m long rests against a wall with one end a short distance from its base. Between the wall and the base of a ladder is a garden storage box 1m tall and 1m high. What is the maximum distance up the wall which the ladder can reach?
V-P Cycles
problem

V-P Cycles

Age
16 to 18
Challenge level
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Form a sequence of vectors by multiplying each vector (using vector products) by a constant vector to get the next one in the seuence(like a GP). What happens?
Dalmatians
problem

Dalmatians

Age
14 to 18
Challenge level
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Investigate the sequences obtained by starting with any positive 2 digit number (10a+b) and repeatedly using the rule 10a+b maps to 10b-a to get the next number in the sequence.