Can you provide me more information why this conclusion is valid?"
"I have no idea why he called."
(1) Are these why-clauses relative clauses?
(2) Is "why" a relative adverb or a relative pronoun here?
(3) I have found "the reason why" (though it's redundant). But can "why" be placed after other nouns as in the above examples?
No, they are subordinate interrogative clauses (embedded questions), though "why" is an adverb. Relative "why" only occurs in relative clauses with "reason" as antecedent. Elsewhere it occurs in interrogatives such as the subordinate ones in your examples.
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No, they are subordinate interrogative clauses (embedded questions), though "why" is an adverb.
Relative "why" only occurs in relative clauses with "reason" as antecedent. Elsewhere it occurs in interrogatives such as the subordinate ones in your examples.
The meanings are:
(1) "Can you provide me with more information about the answer to the question 'Why is this conclusion