Step 1: Basis Fundamentals:
A basis in vector space V is a set of vectors. This set must fulfill two key properties to ensure any vector in V can be uniquely expressed as a linear combination of its basis vectors.
Step 2: Basis Properties Explained:
A subset B of vector space V constitutes a basis if and only if:
B is linearly independent. No vector in B can be created from a linear combination of other vectors within B. This corresponds to statement (C).
B spans V. Every vector in V can be written as a linear combination of vectors from B. This corresponds to statement (A).
Analyzing other statements:
(B) B contains the zero vector: This is incorrect. A set including the zero vector is always linearly dependent, breaking the first basis condition.
(D) B is the unique basis of V: This is also incorrect. Most vector spaces have infinitely many bases. For instance, in \(\mathbb{R}^2\), both \(\{(1,0), (0,1)\}\) and \(\{(1,1), (1,-1)\}\) are valid bases.
Step 3: Conclusion:
A basis has two essential properties: linear independence and spanning the vector space. Therefore, statements (A) and (C) are correct.