adverb
Formal or literary equivalent of なぜ; used in writing, speeches, or elevated conversation.
何故このような結果になったのか、説明を求めます。
I demand an explanation as to why this result came about.
Standard kanji spelling; common in formal and literary contexts.
Mixed kanji-kana spelling; may be easier to read for some learners.
Compound of 何 (nani, 'what') and 故 (yue, 'reason'). The reading なにゆえ is a regular combination of the two components.