释义 |
Harmonic Addition TheoremTo convert an equation of the form
| (1) |
to the form
| (2) |
expand (2) using the trigonometric addition formulas to obtain
| (3) |
Now equate the Coefficients of (1) and (3)
so
| (6) |
| (7) |
and we have
Given two general sinusoidal functions with frequency :
their sum can be expressed as a sinusoidal function with frequency
Now, define
| (13) |
| (14) |
Then (12) becomes
| (15) |
Square and add (13) and (14)
| (16) |
Also, divide (14) by (13)
| (17) |
so
| (18) |
where and are defined by (16) and (17).
This procedure can be generalized to a sum of harmonic waves, giving
| (19) |
where
and
| (22) |
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