Q.E.D.
ABBREVIATION TO INDICATE THE COMPLETION OF A MATHEMATICAL PROOF
Quod erat demonstrandum; Cqfd; Q.E.D; Quad Erat Demonstrandum; Q.E.F.; Quod Erat Demonstrandum; Quod Erat Demonstrantum; Q.e.d.; Q E D; Q. E. D.; Q.E.F; Quod erat demonstratum; Quod erat faciendum; Ὅπερ ἔδει δειξαι; QEF; Proving a point; C.Q.F.D.; Ὅπερ ἔδει δεῖξαι; Quod erat demonstrandom
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