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Mathematics LibreTexts

5: Cosets, Lagrange’s Theorem, and Normal Subgroups

  • Page ID
    97999
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    • 5.1: Cosets
    • 5.2: Lagrange's Theorem
      We’re finally ready to state Lagrange’s Theorem, which is named after the Italian born mathematician Joseph Louis Lagrange. It turns out that Lagrange did not actually prove the theorem that is named after him. The theorem was actually proved by Carl Friedrich Gauss in 1801.
    • 5.3: Normal Subgroups


    This page titled 5: Cosets, Lagrange’s Theorem, and Normal Subgroups is shared under a CC BY-SA 4.0 license and was authored, remixed, and/or curated by Dana Ernst via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.

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