Originally Posted By: Bass Thumper
I think a light bulb went off.
If F Major is F-A-C and F# Major is F#-A#-C#
Then is C# Major C#-E#-G# = C#-F-G#?

And D# Major D#-F##-A# = D#-G-A#?

If so, does the same work Xb Major? Just flatten the notes of the natural major chord notes?

Yes, it works exactly like that.
What's important is the intervals between the notes .. the intervals are always the same on and same type of chord, no matter on what note they start. It's true of all the notes in a chord, including the various 9ths and so on. Notes may sometimes be moved to the same note in a different octave.
Learning how to find them quickly and easily is part of the challenge.

Jazz relative beginner, starting at a much older age than was helpful.
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