92 清大資訊 5% @ Unicorn2 的部落格

Oct 01 Mon 2007 04:44
92 清大資訊 5%

Let Pn denote the set of polynomials of degree less than n , which of the following is a sunspace of P4?

(1)The set of polynomials in P4 of even degree.
(2)The set of polynomials in P4 of degree 3.
(3)The set of polynomials in P4 such that P(0)=0.
(4)The set of polynomials in P4 having at least one real root.

想請問線性代數還記得的人第二個為甚麼不是子空間呢？
（解答說 0 不在那個空間@@）

感謝指教。