This is an immediate consequence of the fact that H is an involutive homography (see InvolutiveHomography.html ). F is the corresponding

Note that the role of C and A

Note also that fixing A

Note that F is on line A

Last remark can be used to give a simple procedure to locate the

See the file RotationOnConics.html for the generation of a homography reminiscent of the usual rotation as a product of two reflexions passing through the rotation center and intersecting there at half the rotation angle.

FregierPolar.html

InvolutiveHomography.html

OscillatingCircle.html

RotationOnConics.html

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