## PHYS345 Electricity and Electronics

**Solving Complex Equations Simultaneously**
Find the mesh currents in the following circuit:

Mesh 1:

(4+j3) *I*_{1} - j3 *I*_{2} = 10 \/20deg
Mesh 2:

- j3 *I*_{1} + (j3-j5) *I*_{2} = 0

MathCAD is an excellent example of a computation tool which is fairly easy to use.
I entered the two equations above to find the complex solution and
with a minimum of effort the answer was provided.

Note that the polar quantity 10 \/ 20deg was converted to 9.40 + j3.42
before entering the equations into MathCAD.

Maple or Mathematica are other programs that you might wish to employ
in finding the complex roots of complex simultaneous equations.
MathCAD runs a subset of Maple; I highly recommend it!

"http://www.physics.udel.edu/~watson/phys345/examples/mathcad2.html"

Last updated Sept. 28, 1998.

Copyright George Watson, Univ. of Delaware, 1998.