Find matrix of the linear function

junsugal
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Homework Statement



Consider the linear function F : P4 -> R5
that sends the basis {1,x,x2,x3,x4} of P4 to the basis {e1,e1,e3,e4,e5} in R5, in that order , that is F(xn)= e(n+1)).
(a) Is this function an isomorphism?
(b) Consider the linear function D : P4-> P4
p(x)->p'(x)

Find the matrix of the linear function T : R5-> R5 such that
(T o F)p(x) = (F o D)p(x)


Homework Equations





The Attempt at a Solution



I solved for part a, but i have no idea how to start on part b
 
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hi junsugal! :smile:

(try using the X2 button just above the Reply box :wink:)

do it for each basis element separately

start with x4

what do you get? :smile:
 
hmm, what do you mean by start with x4?

For part(a) I said that yes the function is isomorphic because P4 and R5 both have dimension of 5. And according to one of the properties of isomorphic, the dimensions of 2 vector spaces should be the same.

Thanks for the tips! :)
 
junsugal said:
hmm, what do you mean by start with x4?

put x = x4 in (T o F)p(x) = (F o D)p(x) :smile:

(and your (a) is ok)
 
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