zài / shù xué / zhèng míng / zhōng / fǎn zhèng fǎ / shì / yī zhǒng / cháng yòng / de / lùn zhèng / fāng fǎ在数学证明中,反证法是一种常用的论证方法。In mathematical proofs, reductio ad absurdum is a commonly used argumentation method.