Chord symbol and Roman numeral for naming an Augmented 6th chord

1. How do you write an Augmented 6th chord?
2. How do you write an augmented chord in Roman numerals?
3. How do you make an augmented 6th?

How do you write an Augmented 6th chord?

Its interval of minor seventh (between root and seventh degree (i.e.: C–B♭ in C–E♭–G♭–B♭) can be written as an augmented sixth (C–E♭–G♭–A♯). Rearranging and transposing, this gives A♭–C♭–D–F♯, a virtual minor version of the French sixth chord.

How do you write an augmented chord in Roman numerals?

In some cases, Roman numerals denote scale degrees themselves. More commonly, however, they represent the chord whose root note is that scale degree.
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Common practice numerals.

How do you make an augmented 6th?

The augmented sixth interval is built from the low sixth scale degree and the raised fourth scale degree. For example, in the key of C, that would be the notes A flat and F#.