Show that the subset X of polynominals in R_{2n}[X] all of whose odd coefficients a_{2i+1}are zero forms a subspace of R_{2n}[X].Describe DDo^{-->}(X) and D^{<--}(X).

Dmean the set of polynomials whose even coefficients are zero, and^{-->}(X)Dmean the set of polynomials whose odd coefficients are zero?^{<--}(X)

Thank you in advance for any help you can provide...