QEF

Etymology 1
From, from.

Phrase

 * 1) “quod erat faciendum”, “what was to have been done” – used to end a mathematical passage other than a proof.

Usage notes
Much less used than. Traditionally used to end passages other than proofs, such as geometric constructions – a “how-to”, not a persuasive argument.

Pronunciation

 * (can be pronounced as an acronym or as an initialism)