单项选择题
A.df（x）dx=f（x） B.df（x）dx=f（x）dx C.（d／dx）f（x）dx=f（x）+c D.（d／dx）f（x）dx=f（x）dx
A.3sin2x+cos2x-3 B.sin2x+1 C.cos2x-3cos2x+3 D.（1／2）cos2x+5／2
A.有拐点 B.无拐点，纵坐标不是极值 C.纵坐标最大 D.纵坐标最小
f（x）dx=f（x）f（x）dx=f（x）dxf（x）dx=f（x）+cf（x）dx=f（x）dxf（x）dx=f（x）f（x）dx=f（x）dxf（x）dx=f（x）+cf（x）dx=f（x）dx