HP HP-11C - Page 143

Section 10: Applications Programs 141
AX = Bis solved by X = CB, viz.,
- 7
Ao Q23 a;; a3 app a3
b, — by + bs
azg Qszy azz ass agzy Qg3
X1
X 1 Qg Qagy a;; a3 a;; a3
2= — - bl + b2 - b3
X3 det A asz ags asz ass ag g3
as; Qg a;; ap a;; ap
b, —by + b3
asz; asg asz; asz agz; Qg
-
Note: -
e Matrix operations can be especially prone to roundoff error. In
certain cases this error may significantly affect the program
results.
e If you have several sets of simultaneous equations to solve,
key in the determinant routine to find the determinants for
each 3 X 3 matrix. Replace the determinant routine with the
simultaneous equations routine and store the respective
determinant in R for each calculation.
a;; ap 0
e A 2X2matrix should bestored as ay; a9 0
0O 0 1
e Error O will be displayed if the matrix entered is singular.