*in which we meet the unitary group and start exploring Möbius maps as transformations of the Riemann sphere.
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# isometries

# Groups Lecture 19

*in which meet the orthogonal group and we rotate and reflect in two and three dimensions.
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# Groups Lecture 20

*in which we rotate and reflect in two and three dimensions, and meet the unitary group.
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# Groups Lecture 19

*in which we act with matrices on vectors and on matrices, and meet the orthogonal group.
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