Keystrokes display – HP 15c User Manual
Page 108
108
Section 4: Using Matrix Operations
108
Solving a Large System of Complex Equations
Example: Find the output voltage at a radian frequency of ω = 15 × 10
3
rad/s for the filter
network shown below.
Describe the circuit using loop currents:
0
0
0
)
(
0
0
)
(
)
(
0
0
)
(
0
0
4
3
2
1
3
3
2
2
2
2
1
2
1
1
1
1
V
I
I
I
I
C
i
L
i
R
L
i
L
i
L
i
C
i
R
R
R
C
i
L
i
R
C
i
C
i
C
i
L
i
R
Solve this complex system for I
1
, I
2
, I
3
, and I
4
. Then V
0
= (R
3
)(I
4
).
Because this system is too large to solve using the standard method for a system of complex
equations, this alternate method (described in the owner's handbook) is used. First, enter the
system matrix into matrix A in complex form and calculate its inverse. Note that ωL = 150,
1/ωC
1
= 800/3, and 1/ωC
2
= 8/3.
Keystrokes
Display
|¥
Program mode.
´CLEARM
000-
Clears program memory.
|¥
Run mode.
0
´m%
0.0000
Provides maximum matrix
memory.
´>0
0.0000
Dimensions all matrices to
0 × 0.
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