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**Rotation around the origin** through an angle :

(*r*,)(*r*,+).

**Reflection in a line through the origin** and making an angle
with the positive *x*-axis:

(*r*,)(*r*, 2-).

*Silvio Levy
Wed Oct 4 16:41:25 PDT 1995*

This document is excerpted from the 30th Edition of the *CRC Standard Mathematical Tables and Formulas* (CRC Press). Unauthorized duplication is forbidden.