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Trig Rules OK

Age 16 to 18
Challenge Level Yellow star
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The problem suggests a property shared by the triangles which always holds no matter how the squares are changed. The challenge is to make and prove a conjecture about this property.

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Polite Numbers

A polite number can be written as the sum of two or more consecutive positive integers, for example 8+9+10=27 is a polite number. Can you find some more polite, and impolite, numbers?

Impossible Triangles?

Which of these triangular jigsaws are impossible to finish?

Least of All

A point moves on a line segment. A function depends on the position of the point. Where do you expect the point to be for a minimum of this function to occur.

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The NRICH Project aims to enrich the mathematical experiences of all learners. To support this aim, members of the NRICH team work in a wide range of capacities, including providing professional development for teachers wishing to embed rich mathematical tasks into everyday classroom practice.

NRICH is part of the family of activities in the Millennium Mathematics Project.

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