周期函数()=A+∑Ansm(AOt+9) k=1 km sin( kot+pu =Akm,(sin kat cos pr+cos kosin k) = Akm cos sin kat+ Akm sin k cos kat -B sin kot+c cos kot f(o0=4+∑ Bkm sin ka+∑CmSo k=1 k=1 = = = + + 1 1 0 ( ) sin cos k km k km f w t A B kw t C kw t 周期函数 ( ) sin( ) 1 0 k k km f wt = A +A kw t + = B k t C k t A k t A k t A k t k t A k t km km km k km k km k k km k = + = + = + + w w w w w w w sin cos cos sin sin cos (sin cos cos sin ) sin( )