4.設f(x)=(x2+2x2+1)(x2+x-1)+2x2+1。選出正確的選項。(A)f(x)除以x+1的餘式為3(B)f(x)除以x2+x-1的商式為x3+2x2+3(C)f(x)除以x2+x一1的餘式為2x2+1 (D)f(x)除以2x3+4x2+2的0餘式為