At grade 4 you will be expected to identify and create root position triads based on the 1st, 4th and 5th notes of the scale (the tonic, subdominant and dominant respectively). These three chords are also called the primary chords and the following videos explain how they are formed.
Start with the first video, which details how the primary chords are formed and how to calculate them for major keys. The second video extends your knowledge by explaining the formation of the primary chords for minor keys.
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