4.16Slash chord does not always mean inversion

Usually it does.

But not always.

For example:

C/D

means:

C major chord over D bass.

Notes might be:

Left hand: D

Right hand: C E G

That is not a normal inversion of C, because D is not a note in C major triad.

It creates a more complex harmony.

We'll get to those later.

For now:

If the slash note belongs to the chord, think inversion.