| Let's take the following example circuit and 
                    analyze it: 
                     The first step is to 
                    determine the reactances (in ohms) for the inductor and the 
                    capacitor. 
 
 The next step is to 
                    express all resistances and reactances in a mathematically 
                    common form: impedance. Remember that an inductive reactance 
                    translates into a positive imaginary impedance (or an 
                    impedance at +90 degrees), while a capacitive reactance 
                    translates into a negative imaginary impedance (impedance at 
                    -90 degrees). Resistance, of course, is still regarded as a 
                    purely "real" impedance (polar angle of 0 degrees): 
                    
  
 Now, with all quantities of opposition to electric current 
                    expressed in a common, complex number format (as impedances, 
                    and not as resistances or reactances), they can be handled 
                    in the same way as plain resistances in a DC circuit. This 
                    is an ideal time to draw up an analysis table for this 
                    circuit and insert all the "given" figures (total voltage, 
                    and the impedances of the resistor, inductor, and 
                    capacitor). 
                     
 Unless otherwise specified, the source voltage will be our 
                    reference for phase shift, and so will be written at an 
                    angle of 0 degrees. Remember that there is no such thing as 
                    an "absolute" angle of phase shift for a voltage or current, 
                    since it's always a quantity relative to another waveform. 
                    Phase angles for impedance, however (like those of the 
                    resistor, inductor, and capacitor), are known absolutely, 
                    because the phase relationships between voltage and current 
                    at each component are absolutely defined.
 Notice that I'm assuming a perfectly reactive inductor and 
                    capacitor, with impedance phase angles of exactly +90 and 
                    -90 degrees, respectively. Although real components won't be 
                    perfect in this regard, they should be fairly close. For 
                    simplicity, I'll assume perfectly reactive inductors and 
                    capacitors from now on in my example calculations except 
                    where noted otherwise.
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