A rotationis the sameas a rotationfollowedby a rotation.If is the matrixfor a polygon,
then
is the matrixfor the imageof in a rotation.Notethat
( rotationfollowedby rotation)is also the imageof in a rotation.
The trianglebelowis rotated
Verticesare , and
Whatare the coordinatesof the verticesof the imagetriangle?
The matrixfor the triangleis