⑩天掌 Teaching Plan on Advanced Mathematics o 傅里叶系数 f∫(x) cos ndx,(n=0,1,2,…) f(x) sin ndx,(n=1,2,… T ∫(x) cos ndx,(n=0,2,) 或 兀0 ∫(x) sinned,(n tianjin polytechnic dmivendityTianjin Polytechnic University Teaching Plan on Advanced Mathematics      =  = =  =    −  − ( )sin , ( 1,2, ) 1 ( )cos , ( 0,1,2, ) 1   b f x nxdx n a f x nxdx n n n      =  = =  =     2 0 2 0 ( )sin , ( 1,2, ) 1 ( )cos , ( 0,1,2, ) 1   b f x nxdx n a f x nxdx n n n 或 傅里叶系数