Add beginning of answers to Axler 5A.

exercises/axler-5a.org

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+#+title: Questions from Axler 5a
+
+3,8,13,35
+
+* Question 3
+
+Suppose \( T \in \mathcal{L}(V)\). Prove that the intersection of every
+collection of subspaces of \(V\) invariant under \(T\) is invariant
+under \(T\).
+
+** Answer
+
+Let \(U_\lambda\) (\(\lambda\in\Lambda\)) be some family of subspaces such that each \(U_\lambda\)
+is invariant under \(T\). 
+
+