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# Complex Puzzle

Recall from Opening the Door that adding a complex number to another number is the same as a translation.

Recall from Into the Wilderness that multiplying a complex number by another is the same as a rotation and an enlargement.

Since $u+v=v+u$ and $uv=vu$, we can decide which complex number we want to 'transform'. For example, for $u+v$, we could start at $u$ and apply a translation corresponding to $v$, or we could start at $v$ and apply a translation corresponding to $u$.

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Age 14 to 18

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- Getting Started
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Recall from Opening the Door that adding a complex number to another number is the same as a translation.

Recall from Into the Wilderness that multiplying a complex number by another is the same as a rotation and an enlargement.

Since $u+v=v+u$ and $uv=vu$, we can decide which complex number we want to 'transform'. For example, for $u+v$, we could start at $u$ and apply a translation corresponding to $v$, or we could start at $v$ and apply a translation corresponding to $u$.