, , . . , , .
(. 2.16, ), L :
.
,
uL, , (uL =- eL).
ϳ i :
(ULm = - w LIm) , UL = - w LI , , , ( ) :
,
xL = w L = 2p fL , , .
( ) :
.
, , , . , , y u = y i + p/2 y i, :
.
( ) , . 2.16, . 2.16, . , y u = 0.
:
p , ( ) , .
p = f (t)(. 2.17) , (WL = LIm 2/2), , . , , , . , 㳿 . 㳿 ( )
, QL, ( ). :