5. 已知a,b為實數,且a≠0,如果一多項式f(x)除以ax+b,得商q(x),餘式為r,試問下列何者正確的?
(A)f(x)除以x+,得商q(x),餘式為r
(B)xf(x)除以ax+b,得商xq(x)-,餘式為
(C)xf(x)除以ax+b,得商xq(x)+,餘式為-
(D)x²f(x)除以ax+b,得商x²q(x)+,餘式為-