A m7/C#
The A m7 chord consists of the A (Perfect unison), C (Minor third), E (Perfect fifth) and G (Minor seventh) notes, with C# as the bass note.

How to play the A m7/C# chord
- Play C# as the lowest bass note in the left hand
- Find A (Root) on the piano keyboard
- Add C (Minor third) — 3 semitones above A
- Add E (Perfect fifth) — 7 semitones above A
- Add G (Minor seventh) — 10 semitones above A
- Press all 5 notes simultaneously to sound the A m7/C# chord