Linear Algebra Field & Vector Space Problem

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The discussion revolves around defining the vector space V as the Cartesian product of two vector spaces V1 and V2, with specific rules for addition and scalar multiplication. Participants express confusion regarding which vector space the operations in the definitions belong to and how to demonstrate that V satisfies the vector space axioms. It is emphasized that understanding the distinction between operations on vectors and those on their components is crucial. The need to clearly articulate how each axiom is satisfied in the proof is highlighted. Overall, the thread seeks clarity on foundational concepts in linear algebra related to vector spaces.
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Homework Statement


Let V1 and V2 be vector spaces over the same field F.
Let V = V1 X V2 = {f(v1, v2) : v1 \in V1; v2 \in V2}, and de fine addition and scalar multiplication as follows.
 For (v1, v2) and (u1, u2) elements of V , defi ne (v1, v2) + (u1, u2) = (v1 + u1, v2 + u2).
 For (v1, v2) element of V and c \in F, defi ne c  (v1, v2) = (c  v1, c  v2).
a) In the de finitions of addition and scalar multiplication there are three "+" and three "." To
which vector space is each one associated with?
b) Show that V is a vector space. NB: you must provide some reason why each of the axioms is
satis ed.


Homework Equations



To be absolute honest i have no idea what it means when it asked which vector space it belong to in part a).
ANd for part 2, i do not know where to start.


The Attempt at a Solution



I know that to proof fields or vector spaces, it has to satisfy with the axioms

Zero vector
addition
scalar multiplication
and etc.
Just have trouble starting this problem

Thanks.

 
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Take, for example, ##\vec{x}+\vec{y}## where ##\vec{x},\vec{y} \in \mathbb{R}^2##. You write ##\vec{x} = \begin{bmatrix} x_1 \\ x_2 \end{bmatrix}## and ##\vec{y} = \begin{bmatrix} y_1 \\ y_2 \end{bmatrix}##. Then
$$\vec{x}+\vec{y} = \begin{bmatrix} x_1 \\ x_2 \end{bmatrix} + \begin{bmatrix} y_1 \\ y_2 \end{bmatrix} = \begin{bmatrix} x_1+y_1 \\ x_2+y_2 \end{bmatrix}.$$ The plus sign between ##\vec{x}## and ##\vec{y}## represents a different operation than the plus sign between ##x_1## and ##y_1##. Why? Because the first one is about adding two vectors while the second one is about adding two real numbers.
 
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