This note gives a more detailed description where the expressions (1.12) for the coefficients , , and comes from.
In terms of the notations for the general case, you have
The introduction noted that the new coefficients can be found from
As an example, let’s find the value for . In terms of the
notations in the general case, is the 1,1 element of matrix :
. To get , put in
The expressions for , and may be verified similarly.