quod erat demonstrandum

Latin phrase quod erat de·mon·stran·dum \ˌkwȯd-ˈer-ˌät-ˌde-mən-ˈstran-dəm, -ˌdā-ˌmȯn-ˈsträn-ˌdu̇m\

Definition of quod erat demonstrandum

  1. :  which (is what) was to be shown (originally) —abbreviation QED —used at the end of a logical or mathematical proof

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