例1-3解签 x(O)是奇的零均值周期信号→an1=0,n=0,1,2,3, b t x(tsin(noot)dt T T J2 x()sin(no,)dt 4CE 2E-1 sin (nott T cos not TJo 2 2E E (1-cosn丌) nrh=1,3,5 0,n=2,4,6, An=bn,9n=-90°X 第 2 页 jh jh 例1-3 ( ) 2 0 2 2 ( )sin d T b x t n t t n T T  − =  2 , 1,3,5, π 0 , 2,4,6, E n n n   = =    = x(t)是奇的零均值周期信号→ an = 0 , n=0,1,2,3, … ( ) 2 0 0 4 sin d 2 T E n t t T =   2 0 0 0 2 1 cos | T E n t T n   − = (1 cos  )  n n E = − ( ) 2 0 0 4 ( )sin d T x t n t t T =   , 90o  = = − A b n n n 