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peripatein
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Homework Statement
Is it possible to add the following subspaces: W_1 = Sp{(1,0,0)} and W_3 = Sp{(0,1,-1), (0,0,1)}?
Homework Equations
The Attempt at a Solution
Will their sum be: Sp{(1,1,-1),(1,0,1)}?
No.peripatein said:Homework Statement
Is it possible to add the following subspaces: W_1 = Sp{(1,0,0)} and W_3 = Sp{(0,1,-1), (0,0,1)}?
Homework Equations
The Attempt at a Solution
Will their sum be: Sp{(1,1,-1),(1,0,1)}?
peripatein said:Mark44, their geometrical representation will be:
W_3 = y-(-z) plane and z axis, W_1 = x axis
peripatein said:R^3.
How may I check whether W_1+W_2=V, where V is a vector space and W_1 and W_2 are two subspaces in V, and W_1=(t,s,t-2s,2t) where t,s belong to R, and W_2=(x,y,z,-x-y-z)?
I first tried to write W_1 as {(1,0,1,2), (0,1,-2,0)} and W_2 as {(1,0,0,-1), (0,1,0,-1),(0,0,1,-1)} and then concluded that since dim(W_1+W_2) was not equal to dim(V) they could not possibly be equal. But I am really not sure that's correct. Could anyone please advise?
The sum of two subspaces is the set of all vectors that can be written as the sum of a vector from one subspace and a vector from another subspace. It is denoted as W = U + V.
The sum of two subspaces is calculated by adding all possible combinations of vectors from each subspace. This means taking a vector from the first subspace and adding it to a vector from the second subspace, and repeating this for all possible combinations. The result is the sum of the two subspaces.
The dimension of the sum of two subspaces is equal to the sum of the dimensions of the individual subspaces minus the dimension of their intersection. In other words, if U and V are subspaces of a vector space W, then dim(U + V) = dim(U) + dim(V) - dim(U ∩ V).
Yes, it is possible for the sum of two subspaces to be equal to one of the individual subspaces. This can happen when one subspace is a subset of the other subspace, or when the two subspaces are identical.
If the two subspaces U and V are linearly independent, then the sum of the two subspaces will be the direct sum of U and V, meaning that there is no overlap between the two subspaces. However, if U and V are linearly dependent, then the sum of the two subspaces will have some shared elements. This relationship between linear independence and the sum of two subspaces can be useful in solving problems involving linear combinations of subspaces.