Dimension of a Direct Sum
88728
Dimensions of vector subspaces in a direct sum are additive
141674
Given $n$ linear functionals $f_k(x_1,\dotsc,x_n) = \sum_{j=1}^n (k-j)x_j$, what is the dimension of the subspace they annihilate?
18415
Direct sum of Abelian groups and Isomorphism
87692
Basis and dimension of vector space
141762
The direct sum of two closed subspace is closed? (Hilbert space)
7785
Cardinality of sum-set
113259
The confusing nature of direct sum for finite abelian groups
125073
Finite-dimensional subspaces of normed vector spaces are direct summands
14429
dimension of a subspace spanned by two subspaces
84871
Determining the dimension of span$\{AB-BA : A,B \in M_{n \times n}(\mathbb R) \}$
121047
Proof: Sum of dimension of orthogonal complement and vector subspace
111911
Dimensions of symmetric and skew-symmetric matrices
70332
Is there a third dimension of numbers?
156479
Fractal dimension of set in $\mathbb{R}^2$
142097
Finding the dimension of the orthogonal complement
54737
Proof that $V = \sum_k U_k$ and $\dim V=\sum_k \dim U_k$ implies $V=\oplus_k U_k$
125184
Why $\dim(\hom(V,W))=\dim(V) * \dim(W)$?