Vector space isomorphic to direct sum

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Let $A$ be a basis for the infinite dimensional space $V$. Prove that $V$ is isomorphic to the direct sum of copies of the field $F$ indexed by the set $A.$ Prove that the direct product of copies of $F$ indexed by $A$ is a vector space over $F$ and it has strictly larger dimension than the dimension of $V.$

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Prove that $V$ is isomorphic to the direct sum of copies of the field $F$ indexed by the set $A$.

This is the definition of basis.

Prove that the direct product of copies of $F$ indexed by $A$ is a vector space over $F$ and it has strictly larger dimension than the dimension of $V$.

Here use Cantor's diagonal argument.