【正确答案】正确答案：由f(x)=f＂(x)一x，可得f(x)cos xdx=f＂(x)cos xdx—xcos xdx =cos xd[f＇(x)]一0=cos xf＇(x)(一sin x)f＇(x)dx =一f＇(π)+f＇(一π)十sin xf(x)cos xf(x)dx =一[f＇(π)一f＇(一π)]一f(x)cos xdx，f(x)cos xdx=一