Now, let us have a look at the A minor scale. The A minor chord is, likewise, composed of the 1st 3rd and 5th notes of the A minor scale. If you have noted, C major and A-minor are relative keys, meaning that they have the same notes composing them; it’s just that A-minor scale can be written as the 6th degree of the C major scale. The notes of the a minor scale are, thus, A, B, C, D, E, F and G. Thus, the A-minor chord has the notes A, C and E. Thus A-minor chord belongs to both the C major scale, as well as the A-minor scale.
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