# Puzzles

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#### Advent calendar 2017

#### Sunday afternoon maths LXII

What's the star?#### Sunday afternoon maths LXI

XYZ#### Sunday afternoon maths LX

Where is Evariste?Bending a straw

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For which complex numbers, \(z\), are \(\mathrm{Re}(z^2)\) and \(\mathrm{Im}(z^2)\) both positive?