### Phasor Notation

The complex amplitude is also defined as the*phasor*associated with any sinusoid having amplitude and phase . The term ``phasor'' is more general than ``complex amplitude'', however, because it also applies to the corresponding

*real*sinusoid given by the real part of Equations (1.9-1.10). In other words, the real sinusoids and may be expressed as

*phasor representation*of is . Phasor analysis is often used to analyze linear time-invariant systems such as analog electrical circuits.

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