## §19.26(i) General Formulas

In this subsection, and also §§19.26(ii) and 19.26(iii), we assume that are positive, except that at most one of can be 0.

where and

19.26.2

with corresponding equations for and obtained by permuting . Also,

where

with and obtained by permuting , , and . (Note that .) Equivalent forms of (19.26.2) are given by

and

Also,

where

19.26.10

Lastly,

where , , , and

19.26.12

Equivalent forms of (19.26.11) are given by

where for , except that can be 0, and

where

## §19.26(iii) Duplication Formulas

The equations inverse to and the two other equations obtained by permuting (see (19.26.19)) are

and two similar equations obtained by exchanging with (and with ), or with (and with ).