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theorem

n. · v.
US //ˈθɪɹəm// UK //θˈiəɹəm// the·o·rem
  1. 1 proven math statement (n.)
    B2 Upper Intermediate Math

    a mathematical rule or statement that has been proven to be true using facts and logic.

    a mathematical proposition of significant importance that has been demonstrated to be true through a formal proof.

    Example

    In school, we learned how to use Pythagoras' theorem to find the length of a triangle's side.

    Example

    The mathematician spent decades attempting to provide a definitive proof for the theorem, which had remained a conjecture since the seventeenth century.

  2. 2 logical deduction (n.)
    C1 Advanced Technical Academic Logic

    a statement in logic that follows correctly from a set of starting rules.

    a formula or statement within a formal system that is derived from the axioms of that system by applying its rules of inference.

    Example

    The computer program checked if the new statement was a valid theorem of the system.

    Example

    In formal logic, a theorem is distinguished from an axiom by the fact that it must be derived through a sequence of valid transformations.

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  1. 3 to make into a theorem (v.)
    C2 Proficiency Technical Formal Math

    to turn a mathematical idea or rule into a formal theorem.

    to formulate a proposition or set of observations into a formal mathematical theorem.

    Example

    The researcher attempted to theorem the observed patterns in the data.

    Example

    The author sought to theorem the preliminary findings, though the complexity of the variables made a formal proof exceptionally difficult to construct.

    Usage

    This verb is rare and almost exclusively found in academic or historical mathematical texts.

Origin

From Middle French théorème, from Late Latin theōrēma, from Ancient Greek θεώρημα (theṓrēma, “speculation, proposition to be proved”) (Euclid), from θεωρέω (theōréō, “I look at, view, consider, examine”), from θεωρός (theōrós, “spectator”), from θέα (théa, “a view”) + ὁράω (horáō, “I see, look”). See also theory, and theater.

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