You mean this part?
"Theory
Impedance is the opposition by a system to the flow of energy from a source. For constant signals, this impedance can also be constant. For varying signals, it usually changes with frequency. The energy involved can be electrical, mechanical, magnetic or thermal. The concept of
electrical impedance is perhaps the most commonly known. Electrical impedance, like electrical resistance, is measured in
ohms. In general, impedance has a
complex value; this means that loads generally have a
resistance component (symbol:
R) which forms the
real part of
Z and a
reactance component (symbol:
X) which forms the
imaginary part of
Z.
In simple cases (such as low-frequency or direct-current power transmission) the reactance may be
negligible or zero; the impedance can be considered a pure resistance, expressed as a real number. In the following summary we will consider the general case when resistance and reactance are both significant, and the special case in which the reactance is negligible."
That is just general impedance theory. It has nothing to do in particular to conjugate match theory.That text was not spaced well. The bold text is applicable
ONLY to what immediately follows it. On subject is basic
Theory the next is
Reflection-less matching followed by
Complex conjugate matching etc.
