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Solving the complex equation ax = b – HP 15c User Manual

Page 169

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Section 12: Calculating with Matrices 169

4. Recall the descriptor of the matrix representing A into the display.

5. If the elements of A were entered in the form of A

C

, press ´

p to transform A

C

into A

P

.

6. Press ´> 2 to transform A

P

into Ã.

7. Designate the result matrix; it must not be the same as the matrix

representing A.

8. Press ÷; this calculates X

P

. The values of these matrix elements

are placed in the result matrix, and the descriptor of the result matrix
is placed in the X-register.

9. If you want the solution in the form X

C

, press |c.

Note that you don't transform B

P

into .

You can derive the complex elements of the solution X by recalling the
elements of X

P

or X

C

and combining them according to the conventions

described earlier.

Example: Engineering student A. C. Dimmer wants to analyze the
electrical circuit shown below. The impedances of the components are
indicated in complex form. Determine the complex representation of the
currents I

1

and I

2

.

This system can be represented by the complex matrix equation

0

5

30)

(200

200

200

200

10

2

I

I

i

i

i

i

1

or

AX = B.