A.(-∞,0)B.(0,π)C.(π,4)D.(4,+∞)
A.B.C.D.
若f(x)dx=F(x)+c,則xf(1-x2)dx=()
A.1/2F(1-x2)+cB.-1/2F(1-x2)+cC.2F(1-x2)+cD.-2F(1-x2)+c