⑩天掌 Teaching Plan on Advanced Mathematics o f(r)sinned 元 (1)sin nxx+-1 sinned 元 元 2 1-(-1)" n兀 n=1,3,5 n兀 0,n=2,4,6, tianjin polytechnic dmivendityTianjin Polytechnic University Teaching Plan on Advanced Mathematics − =    bn f (x)sinnxdx 1   = − +  −     0 0 1 sin 1 ( 1)sin 1 nxdx nxdx [1 ( 1) ] 2 n n = − −      = = =   0, 2,4,6, , 1,3,5, 4 n n n