Quod Erat Démonstrandum

Pronunciation: /kwɑd ærɑt dɪ.mɒn.stræn.dʌm/ Explain
Abbreviation: QED

Q.E.D. is an abbreviation placed at the end of a proof. It comes from the Latin phrase quod erat démonstrandum which means 'That which was to be proved'.


  1. McAdams, David E.. All Math Words Dictionary, quod erat démonstrandum. 2nd Classroom edition 20150108-4799968. pg 147. Life is a Story Problem LLC. January 8, 2015.

Cite this article as:

McAdams, David E. Quod Erat Démonstrandum. 12/21/2018. All Math Words Encyclopedia. Life is a Story Problem LLC. https://www.allmathwords.org/en/q/qed.html.

Revision History

12/21/2018: Reviewed and corrected IPA pronunication. (McAdams, David E.)
12/3/2018: Removed broken links, updated license, implemented new markup. (McAdams, David E.)
9/4/2007: Added 'More Information'. (McAdams, David E.)
7/12/2007: Initial version. (McAdams, David E.)

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