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Rotating real-valued functions in the plane. (English) Zbl 1337.97011
Summary: Let $$f$$ be a real-valued function defined over a subset of $$\mathbb{R}$$. In the following article, we investigate the graph of $$f$$ under rotation by a fixed angle about the origin. In particular, we give necessary and sufficient conditions on the angles of rotation which result in an image that still describes a function. We include several illuminating examples and use the converse of the mean value theorem to extend previously known results.
##### MSC:
 97I20 Mappings and functions (educational aspects) 97I40 Differential calculus (educational aspects) 26A06 One-variable calculus
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##### References:
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