In accordance with the definition of the matrix product, it follows from (62): 
7 
(1) Ay Qu + AjaQ 2° 
8 
pd 
(2) Au Qi2* Aj120225 O 
T T 
(3) | Ai2Qqu t Aga Qj2 50 
T 
(4)  AgQ,2* Ao5055*T 
With (65) we obtain: 
i 
Quo *7Aq AQ, 
or 
T T 4 
Ai2 Qi2 * 7 A2 Aj Ajo Qo 
T ' T a= A 
Ai2Qi2*. Ag2022 *(63)4 = I * (A55- Aio Ai] Aug) Q22 
or 
| d "d 
Q22* ( Aga 7 Ajo Aq Aja 
=| 
Formula (64) is identical with the corresponding expression AS in formula 
(28), which had to be proven. 
In order to compute the mean errors of those parameter corrections , Which 
&re eliminated during the process of forming reduced normal equations, ac- 
cording to formulas (37) or (38), the matrices Q(jor Qoo, respectively, must 
be obtained. It follows from formulas (65), equations (1) anà (2), that 
- -l T ,-l (65 
Qu 75] * Ad Ap Qoo Aio Ay ) 
43