what are the "formulas" for these chords???

sorry about all these questions on chords, but my bass book only goes so far....

one more question. what is a dom chord?

C7 = 1,3,5,b7 (C,E,G,Bb)
C9 = 1,3,5,b7,9 (C,E,G,Bb,D)

A dominant chord is a "7" chord, like the one above, but can be extended to 9,11, or 13. It functions as the "5" chord, who's strongest resolution is to the tonic. So named because it is the chord built off the the 5th scale degree of a major scale (called the dominant).

the diff between DOM 7th and major 7th is the b7....a major 7th is like this C-E-G-B.
since I could see that as being a follow-up question.
pacman did a pretty good job explaining it though

what's so crucial about the dominant-tonic relationship is how the notes resolve...the voice leading.

an example in C:

G7 CMaj

F e

d b

b C

G G

the half step magnetism from the 3rd and 7th of G to the root and 3rd of C (respectively) is what makes the dominant 7th chord so powerful.

yummy, theory.

there's more...but, most people get a glazed look hearing about this stuff.

f

bump