*in which we use actions to find sizes of groups, subgroups and stabilisers, and prove Cauchy’s Theorem.
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# Lagrange

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# Groups Lecture 14

*in which we meet several standard actions and prove Cayley’s Theorem.
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# Groups Lecture 10

*in which we apply group theory to prove Fermat-Euler, use Lagrange to help us find subgroups or determine what a small group must look like, and meet normal subgroups.
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# Groups Lecture 9

*in which apply Lagrange’s Theorem to prime order groups, meet equivalence relations and further explore multiplication modulo n.
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# Groups Lecture 8

*in which we show that the sign of a permutation is a surjective group homomorphism, meet cosets and prove Lagrange’s Theorem.
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# Groups Lecture 15

*in which we meet conjugation in several forms, and learn that lecturers are not infallible.
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# Groups Lecture 14

*in which we meet orbits and stabilisers and prove the Orbit-Stabiliser Theorem.
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