The previous post showed Root triads in individual Zone positions forming stacks of 4ths. Here we'll look at the 1st and 2nd Inversion forms.
The 1st Inversion triads are formed by moving the root to the top (highest pitch), the 3rd is the low note and the 5th is in the middle of the triad.
In the diagram below, If we read the "I" as the note G on the 3rd fret on the 6th string:
... then the first chord in the VII Zone (reading from the bottom of the Zone) is an F# diminished. Though the II of the key is the low note, the VII of the key is the root of this triad, as the high notes in all these triads are their root notes.
The green triad in II Zone is the Tonic chord since it has the high note of "I" even though its low note is III, etc ...
Here's TAB and notation for the 1st inversion triads in the key of G:
2nd Inversion triads are formed by moving the root to the top (highest pitch), then placing the 3rd above it. The 5th is now the low note and the Root is in the middle of the triad.
In the diagram below, If we read the "I" as the note G on the 3rd fret, then the first chord in the VII Zone (reading from the bottom of the Zone) is a C major. Though the I of the key is the low note of this triad, the IV of the key is its root, as the middle notes in all these triads are their root notes:
Here's TAB and notation for the 2nd inversion triads in the key of G:
Inversions can be found within a Zone by starting with a root triad and either raising the 5th or lowering the root to the next degree of the key. Raising the 5th of any triad to the next key degree will turn the triad into a 1st inversion ... rather than refer to the raised 5th as a "6th", it becomes the root of the chord.
For example: An A minor triad contains the notes A C and E. Replacing the E with F# we now have the notes A C F#, An F# diminished triad with the root as the high note — a 1st inversion F#ยบ. Likewise, that same A minor triad can have its Root replaced with the note G — one key degree down from the original root note. Now the G becomes the 5th, the C is the Root and E is the 3rd of a C major chord, which functions as the IV chord in the key of G.
Apply this principle to all the root triads ... and then reverse the process. Any 1st inversion triad can have its hight note (root) lowered to the next key degree down and become a Root Triad, and any 2nd inversion triad can have its low note raised to the next key degree up and that note will be the new triad root.