Exercise · ZW-FORMAL-PROOF-002 · ★☆☆ Basic

Each line of a formal proof must be...

Choose one option.

Show answer

C. An axiom, allowed hypothesis or consequence of a rule

Explanation

Every line must be justified by an axiom, an allowed hypothesis or a rule applied to earlier lines. The other options are not logical lines.

Open the ZWMath map →

Review the concept: Formal proof

A formal proof of \(\varphi_n\) is a sequence \(\varphi_1,\ldots,\varphi_n\) in which each term is an axiom, an admitted hypothesis, or the result of a rule applied to earlier terms.

\[\varphi_1,\varphi_2,\ldots,\varphi_n\vdash\varphi_n\]

Each line of a formal proof must be...

Explanation

Review the concept: Formal proof

More practice problems: formal proof