2.II.10E

Linear Algebra
Part IB, 2006

Suppose that VV is the set of complex polynomials of degree at most nn in the variable xx. Find the dimension of VV as a complex vector space.

Define

ek:VC by ek(ϕ)=dkϕdxk(0)e_{k}: V \rightarrow \mathbf{C} \quad \text { by } \quad e_{k}(\phi)=\frac{d^{k} \phi}{d x^{k}}(0)

Find a subset of {ekkN}\left\{e_{k} \mid k \in \mathbf{N}\right\} that is a basis of the dual vector space VV^{*}. Find the corresponding dual basis of VV.

Define

D:VV by D(ϕ)=dϕdx.D: V \rightarrow V \quad \text { by } \quad D(\phi)=\frac{d \phi}{d x} .

Write down the matrix of DD with respect to the basis of VV that you have just found, and the matrix of the map dual to DD with respect to the dual basis.