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Proof Notation

This video presents the same text shown beside it, spoken and on screen. It adds nothing the text does not say.

State

Number every line. Justify every derived line by citing the lines used and the rule applied.

Show

4. Q 1, 3, MP — line 4 is Q, obtained from lines 1 and 3 by modus ponens.

Watch for

A line without a justification isn't a proof step; it's a wish.