Linear transformation defined by T(a + bx) = (a, a+b)

jeff1evesque
Messages
312
Reaction score
0
Example
Let T: P_1(R) --> R^2 be the linear transformation defined by T(a + bx) = (a, a+b).
The reader can verify directly that T-1: R^2 --> P_1(R) is defined by T-1(c, d) = c + (d-c)x. Observe that T-1 is also linear.

I am reading my text and it kind of makes sense, but I have no clue how to verify what has been said above. It make sense to reverse everything, and because after the reversal since the inverse doesn't have the element c for the second element in the order pair for R^2 then we subtract it from the image of T-1? But I don't feel comfortable with the concept (of this reversal-and subtraction), and I don't know how to verify what has been said.
 
Physics news on Phys.org


If (c, d) is an element of the range of T (and thus the domain of T-1), then c = a and d = a+b for some element (a + bx) in the domain of T. This should start you in the right direction.
 


slider142 said:
If (c, d) is an element of the range of T (and thus the domain of T-1), then c = a and d = a+b for some element (a + bx) in the domain of T. This should start you in the right direction.

Thank you,

JL
 
##\textbf{Exercise 10}:## I came across the following solution online: Questions: 1. When the author states in "that ring (not sure if he is referring to ##R## or ##R/\mathfrak{p}##, but I am guessing the later) ##x_n x_{n+1}=0## for all odd $n$ and ##x_{n+1}## is invertible, so that ##x_n=0##" 2. How does ##x_nx_{n+1}=0## implies that ##x_{n+1}## is invertible and ##x_n=0##. I mean if the quotient ring ##R/\mathfrak{p}## is an integral domain, and ##x_{n+1}## is invertible then...
The following are taken from the two sources, 1) from this online page and the book An Introduction to Module Theory by: Ibrahim Assem, Flavio U. Coelho. In the Abelian Categories chapter in the module theory text on page 157, right after presenting IV.2.21 Definition, the authors states "Image and coimage may or may not exist, but if they do, then they are unique up to isomorphism (because so are kernels and cokernels). Also in the reference url page above, the authors present two...
When decomposing a representation ##\rho## of a finite group ##G## into irreducible representations, we can find the number of times the representation contains a particular irrep ##\rho_0## through the character inner product $$ \langle \chi, \chi_0\rangle = \frac{1}{|G|} \sum_{g\in G} \chi(g) \chi_0(g)^*$$ where ##\chi## and ##\chi_0## are the characters of ##\rho## and ##\rho_0##, respectively. Since all group elements in the same conjugacy class have the same characters, this may be...

Similar threads

Back
Top